BTW, we don't have a classified section in this Track forum. But there is one in Single Speed / Fixed Gear. They use lots of track gear that we could also use.

Have a look:

Disclaimer: I (or bikeforums) cannot vouch for anyone there. This is still the internet. Buyer Beware.

That being said, I have bought and sold track racing gear there before. No complaints. You have to have an upgraded membership to post things for sale. But anyone can contact the sellers.