Kahel Stormbender |
To my knowledge, the answer is no variants. Mistmail is a very specific named magic item, for example. And it's always the same type of armor, made from the same materials.
I might be wrong though, so I'd suggest waiting for someone more knowledgeable then me.
You can have custom magic items. Such as an amulet of protection/mighty fist. But it's far more expensive. It also requires using the PFS rulings on upgrading your magic items. Which are quite specific about being unable to do things like turn a vanilla +1 chainmail into Mistmail. This would imply that no, you can't have full plate mistmail either. Or you can't turn a +1 vanilla dagger into a dagger of venom.
Nefreet |
Detailed breakdown of how to upgrade your gear in PFS.
TL;DR - custom items are generally not available in PFS.