im stuck

Try to think what his hobbies are. Maybe you could get ideas from that. Does he like watching videos? Play golf? watch sports? like to travel? Does he have a collection? Stuff like that.

If you are struggling, then maybe it would be a good idea to just buy him a gift card for a store so that he could go out and buy something that he picks out for himself. Another idea might be just to browse around at some of his stuff and then go on ebay and type in that item. If he likes a certain ball player or race car driver, then maybe you could buy him some memorabilia of that player. Sometimes you can get autograghed baseball card really cheap. Or if he has a favorite team, I don't think guys can have enough shirts and hats of their favorite sports team. I hope these ideas are helpful. Good luck to you and have a great day!