buddy 125 2v performance head with race cam $90 (must use race exhaust system)
I can get exhaust systems and they are cheap but im concearned about postage costs, show me a design and i will get you a price.
all parts are by RRGS, there are cheaper companys out there but these guys are regarded as the best quality in taiwan.
buddy 125/150 aftermarket suspension, ignore the posts with suspension below if you have a buddy as RRGS do a special one designed for your bike and its cheaper!.
design is the same as the first shock below and price is $140.
150 engine kits coming up shortly

UPDATE
ok it seems genuine screwed up when choosing the engine for the 150, you see there are 3 versions, a 2 valve 147cc, 2 valve 149cc and a 4 valve 149cc.
both the 149ccs are much more tunable, you can go 180cc with a bolt on kit and over 200cc if you do the bottom end.
which brings me to the bad news, the 147cc just isnt tunable, best you can do is 59.5mm on the piston which takes it to a modest 160.7cc.
so cc wise your kind of stuck, but you can upgrade to a 4v head with a 160cc kit, if this is of any interest i will pursue and get prices otherwise i will leave it be!.