Small block hei distributors
Avoid the dist in post #2, it does NOT have an adj VA unit.
Get the large cap HEI, coil-in-cap. I can buy the Chinese ones here for $60 for A Chebby, bit more for other brands; have used heaps of them, never had a problem. In fact the only problem I had was one that I upgraded with a Summit 4 pin module with adj rev limiter. This module failed & was replaced by the original module, all working well now.
These dists are well made, centre plate & weights are chromed to prevent rust & are lubricated well. Weights etc are same set up as factory GM. They also come with adjustable VA unit.