Hi from Perth
I've also got a 2007 K1200LT
Over here, Munich Motorcycles is the go to place for any BMW parts. https://www2.munichmotorcycles.com.au/index.php
. They're always very helpful and very experienced with a pretty extensive range of stock. Having said that, I've never had to buy anything specifically for the K1200LT from them. I also have a 1970 BMW R60/5; I've bought heaps of stuff for it from them.
Most other things I've installed I think I've generally done the research on this forum and often gone to the manufacturer website direct.
Overseas, I've found that both Moto-Bins (https://www.motobins.co.uk/
) and Motorworks (https://www.motorworks.co.uk/vlive/Home/index.php
) have been very responsive. I can't remember what I ordered from, I think Motor Works, but I was stunned when it arrived two days later! To get anything from the other side of the world to Perth in two days is amazing.
In the US, Max BMW (https://www.maxbmw.com/
) quite often pops up as a pretty good source for parts and info on this and other BMW forums.
For the parts you're looking for, the fairing fasteners and rubber blind rivet nuts might be available from Munich Motorcycles; if not, they would probably be able to point you at a source.
Can't even begin to start thinking where you would find a mirror for the top case. Maybe some one has one tucked away or it might be available from BMW itself, at a premium of course.
Same for the little lock on the fuel cap flap. It's some sort of little magnetic thing. Mine was very intermittent when I bought the bike. Sometimes it would do what it was supposed to do, other times not. Then it stopped working completely. I never worried about it after that except maybe "one day", I'll do something about that. Then late last year it decided to start working again and has worked perfectly ever since.
I looked at your picture (great looking bike by the way) and yes, the little back support is missing on the front seat. I wonder why that was done? Guess you could get it remade or you may have to find a second hand one?
I've added GPS, running lights, auxiliary driving lights, USB power in the glove box and auxiliary input into the stereo system. I'm not a fan of just throwing another wire onto the battery with an inline fuse hidden somewhere that I'm sure to forget. I installed a Fuzeblocks FZ-1 Distribution Block (https://www.fuzeblocks.com/
) under the seat and use that to provide power to the GPS and USB power outlet and to provide switched power to the relay for the auxiliary driving lights.
Mounting lights can be a bit challenging; a lot of plastic and not many apparent solid mounting points unless you're a good fabricator. I mounted a pair of PIAA 1100X on PIAA mounting brackets (PIAA | Bmw K1200LT Sport Touring Bracket Kit #74121
) under the nose cone. I'm not sure if those lights or brackets are still available. If I was doing it again, i'd go down the LED route. There's so many good options out there I wouldn't know where to start. I'm sure you'll find more up to date recommendations for lighting on this forum. I think I have a pair of the mounts in my collection of stuff. Don't know why I ended up with two pair but they're yours for cost of postage if you want them.
I mounted a pair of HID lights to under mirror mounts. I may replace them if I get round to it. Some dodgy brand and while the lighting is great (described as looking like a jet about to land on an aircraft carrier when coming down the road with everything on), one of the provided ballast didn't work from day one and the other failed within the first month. Replaced with ballast from Phillips and no problems since then. Also the finish on the light bodies has not held up; very poor considering I didn't ride the bike all that much or in poor weather back then.
The under mirror mounts were from BMR Products. i don't think they exist anymore but if you look at Clearwater Lights, the mounts used on the Darla kit for the K1200LT are identical. (https://www.clearwaterlights.com/col...s/bike_k1200lt
Anyway, good luck pulling everything apart. Pulling all the fairing off is a bit of a battle the first couple of times but pretty straight forward really as long as you can keep track of where everything goes. Some people on this forum describe using a peice of cardboard with a rough picture of the bike on it. Punch the fasteners through the cardboard in their rough position on the bike. One trap that bit me was the four screws around the glovebox latch. One of the screws is shorter than the other. If you put a longer one back in that position it will block the electric lock and you will not be able to open the glovebox. Lots of head scratching when I did that.