There isn't a pawn shop in the UK you might get in contact with?

The ones in Toronto work pretty much the way they do on TV shows.

Also it might be noteworthy that some pawn brokers deal only with jewelry/gold/that sort of thing. And others will buy almost anything. The last one I went to had everything from ukuleles to old Nintendo games to high school text books.

There are used record shops, clothing shops, book stores and so on that operate in pretty much the same way.

It may make more sense to think of them as "consignment" shops.