Anyone w/SuperTrapp can confirm Model number?

Hi all - if anyone has a SuperTrapp exhaust for a 1983 VF750F or even a 500 could you check the model number? The ones I have that I bought off eBay recently have a model number 4 MSR-30751L but from putting them up against the side of the existing exhaust the mounting hole looks too short. I'm thinking that maybe the eBay listing incorrectly listed them for a 750 when they actually belong to a 500?

I can provide some measurements of the SuperTrapp exhaust too if that helps.

Thanks!!