Did you give ebay a look yet. I know that there have been a few Vortec manifolds on there recently, used and new. Just make sure you know what they're worth new, or some dumba$$ will bid them over what they're worth. Self-aligning roller rockers(not roller tip) are always on there new for about $170. Check out www.northernautoparts.com as well, they have decent prices. As a side note, I bought all of the aftermarket parts for my 383 from my local engine builder for the same price as Jegs, Summit and Northern auto parts.