I just installed that 1st aid kit on my E86 M Coupe. #3 the mounting bracket was available for order from my local dealer. Ordered it 2 Saturday ago, and picked it up last Saturday (was ready on Wednesday). About $10 w/ BMW CCA discount. Painful trying to install it, but that car really has no storage, so adding that is a big plus.
You can also order the entire thing from leatherZ.
Current: '13 E92 M3 Euro Delivery 9/4
Wife's: E39 M5, E36 M3, E30 M3
Gone: E86 M Coupe