There's a guy named Bill Laney of max wedge performance in Australia that can cast you pretty much any manifold you want. You name the heads, engine, blower(4-71/6-71..etc) and he pops one out like magic. It's nuts. I don't know if he'd do a whipple, but you could always ask. Just google his name.
For instance:
SB chrysler intake for a 6-71 with 302 heads
