Ive got a complete top end off of a SFV650 Gladius for sale.
Everything is there, barrels, heads, pistons, pins, circlips, bolts etc, the only thing missing is 1 of the cam covers but they are easily available on Fleabay (other auction sites are available!)
I believe that they will fit all twin spark engines and that the cams are more aggressive so give a bit more HP, please do your own checks though.
I've got them for sale on Fleabay Suzuki Gladius SFV 650. SV650 Mini Twin Heads and Barrels etc | eBay
I'm in England but will send them worldwide if the buyer pays the shipping