Jim, here's a tip to help you practically guarantee that £50 in your pocket. Just put "819 line French television system" in Google and you'll get over 100,000 responses... many of them actually useful!
As for a Wobulator, that seems to have quite a few different meanings other than oscilloscope, among them a guitar pedal effect. I like the B-movie idea best, though.
Good luck collecting the money!
Tom