Please write down your hot tips for where to get close to the original wires on the K looms. Come winter, I'll be redoing mine, and I want the thin types that BMW used. Unfortunately, I can't seem to find anyone who stocks decent amount of colors/sizes...

Don't really like being a wet blanket but a few years ago I enquired about it and could buy the right colours but had to get 1000meter rolls minimium So I ended going to a wrecking yard and bought some wiring harnesses out of cars and got everything I needed.
If you can find someone who manufacturers the harnesses for one of the car manufacturers then they may sell some colours.

There have been several members here who's harnesses have been cut and hacked.  They may have bought replacements meaning their old harnesses may be available.  Put an ad in the Buy/Sell section.

Another source is Motobins.  They are offering K75 upper and lower harnesses on their clearance page.  At 40 GBP for the upper and 25 GBP for the lower, this will definitely be cheaper than raw spooled wire (not to mention reserve connectors).

Thanks guys! 
Those harnesses from Motobins might just work. Didn't really think of that, but that's why I ask  

I'll keep looking...

No big deal.

First buy the base color wire.
Then, add striping by wrapping some masking tape around the wire diagonally but leaving a stripe unmasked. Use a spray can of your choice of color and paint the exposed stripe.
Let dry overnight.
Presto--a properly striped wire!

We know where you are (your transponder chip is telling us) just remain calm and the nice men with the rubber truck will be there soon to help you.

Oh, I'd like that 

With motorcycle wiring unless you are going for some Concours prize with all original bits you are better off going to thicker conductor wiring rather than staying with thin. That way you have more options for buying cable.
Regards,
K-BIKE