The Marine Mammal Protection Act has been around since 1972.it is nothing new.I don't think it was truly legal to sell seal skin when we could get it.My recollection is that the only time you could buy Native harvested marine mammal parts was when it incorporated some kind of native art like scrimshaw on ivory.When I bought seal from archery suppliers,it had a machine stitch line on one edge.I think this was to get around the law and say that it was native art.I truly suspect someone put their foot down.
Purchasing wildlife parts can be tricky and there are laws,state and federal.It is legal to purchase things that were made before a ban like this,if it can be documented that it is pre-ban.
I think there are plenty of options for arrow rests and sideplates and I think a lot of options have been overlooked.The hair on the shins of many hoofed animals is slick and tough,for a reason and I bet it would make excellent rest material.Looking at a variety of animals including African,one could come up with about any hair length and color he wanted.A mountain of this stuff is discarded every year.Your local taxidermy shop might be a good place to check.