that's not true Wes, I have a pre unit tack drive somewhere that is tapered to fit into a unit cam. I got it in some parts from Danny Macias .I have run a unit exhaust cam on my 500cc pre-unit Triumph for 8 years and never had a problem. Problem comes when you wanna add a tach drive cover. No way to drive it.
Yes, you sure could.A skillful guy could make that from an auto advance bolt with weld added the head and hand ground to rough shape and then"turned" to shape in a drill press. and the slot cut with a hacksaw.
Did you use PayPal? If so just complain and you'll get the money returned..WTF! is wrong with these people, so the 'usable' cams arrive from fleabay seller. Staining i can live with, pitting on the lobe is just totally FUBAR.
'call if not completly satisfied, don't post negative feedback', Damn right you'll pay return shipping if you want this piece of crap back.