I have a used STM slipper clutch for a Husqvarna 450/510 04-07 and it may fit the 08 model also. You would need to check with STM on that one. It has two supermoto races on it and the rest of the time on the street in my 07 Husq 510 SMR. total 2000km. I have the box and all the instructions. Works great. Brand new they are $1200. I am asking $600. PM or call .
Thanks for looking