https://www.shapeways.com/product/F2ZX6CQNK/acc-14-supspider-gear-6inch-v1-4
So I found these while I was browsing through different Spider-Man custom figures (Yes, I know, I have a problem.) I noticed the same legs being used by a couple of different customs. Turns out they're actually 3D prints, designed for use with Superior Spider-Man customs (the set also includes the wrist gadgets, which were apparently missing from the main release). That said, I've also seen them on some pretty amazing Iron Spider customs as well (thout I'm a bit sad he doesn't sell the set in Yellow for that reason).
Personally, I only really want the wrist gauntlets for whenever I DO buy Spider-Ock (the legs look fun as hell, but long-term they're likely just space wasting), but I know a few other people were collecting Spider-Man toys, and I thought I'd share them.
I thought it was bizarre and disappointing that the Superior Spider-Man figure didn't include the legs. It's the key component to the design.