Randy, I've seen some servo hatches on a few web sites. I'll research and find them for ya. They looked like they were a lot better made. I think it was HobbyLobby but not sure.
They were made by Gruapner iI think. Looks like you have to do a total time airframe rebuild for your Transall. That plane is in the air a lot LOL. Probably more total flight time than most Transall's out there.

Pete