Drive yourself out to farm or ranch country and spin your AM radio dial until you find the local station that sells veterinary remedies and reports on commodity markets instead of Wall Street. Find out when their "trading post" or some such program is on the air. If you call in with something good enough to trade, you're likely to find most anything you're looking for.
It's probably a pretty good way to find somebody's "junk" sewing machine in exchange for a few laying hens or a washer or dryer.
Do you have radio markets like this in England? I find them great entertainment.
Max