Cams do turn up. If you can identify other machines that are the same basic design as yours that have cams with them it will give you a good idea of what you are after. We've started to build a database for cams and the machines that they fit in "The Cam Thread" just for this reason. You're nowhere near being alone in having a machine with no cams that fit.
Watching you build one would be interesting but realistically patience and persistence in searching Ebay ads will eventually get you a set-probably with far less effort.
Rodney