Hello Jamie,
(Welcome to RootsChat ... we do hope you take up an interest in your family history ... it can become quite an addiction !)
Would you possibly consider selling the theatre stuff separately (as I know there's a market for that) and sorting the rest out and allowing us RootsChatters to see what we can find out for you, and find the rightful home for the stuff ? We've done it before, with great success. (Here's a tempter ... ) if you are a regular eBay seller, it could be good publicity for you !