CoRoMo
Member
When do you think I should contact them to see if they found anything?
Immediately and continuously.
You have to realize that searching for a history of that gun is nobody's priority at all. It will sit on a desk or in a locker for infinity until you pester them into doing a search. They might not even know how to go about it in the first place since it has no serial number, and since it is so old and uncommon.
If they can't find anything on the gun, don't know how to research the gun, etc. you need to ask for it back ASAP. They might deny you because they "still need to do some digging", but that might go on forever.
If I were in your shoes, I would honestly call them every day if it were something I wanted to get back in a bad way. This particular gun might be expendable though.