Something even better. Set a maximum price in Ebay and search for "oscilloscope".
I mean seriously it's not that hard. Or just search for something then paste &_udhi=50 at the end of the url.
There is no point in posting all the auctions that have bid of $50, as the auction ain't over yet.
Then there is the fact that posting here will if anything drive up the price, possibly even artificially inflating it.
Do you also really want to recommend auctions that could end up being a pile of junk?
I stopped counting at about 70 scopes under $50 just part way down the first page.
Sorry to spoil your fun but this is why I get paid the big bucks.