I bought tanned hides and some other stuff that had animal parts and brought them back without issue. Souvenir shop should give you paperwork for any of that. I got ostrich eggs, porcupine quills, wart hog tusks, carved horns. But I will comment that the customs guy I got in Newark was very thorough, he went through every single item in my suitcase and carry on. Basterd took the 2 pounds of biltong I hoped would go unnoticed in a full bag lol. No big deal though, they don't fine you or anything so its worth a shot in my opinion lol . Tanned hides are no problem in carry on or suitcase