I have one off ebay, and it doesn't do much really. Just got a mid range cam. IMO, it's not worth the money you pay. Mind you, if you are Carb'ed then by all means go for it , just wasn't any good for F.I.
there are several places that i know of,fastfreddy's offers 260 & 270 duration w/ .420 valve lift $338 w/lifterscolt camshafts & kits in british columbia, not sure of their specs or pricesand on e-bay every now and then for $150-250.