here's a cheaper new alternative to ACDelco. Quit a few on here have used these with great results...including me. Just search the forums for Skip White for reviews.
https://www.skipwhiteperformance.co...0-383-super-65k-hei-distributor-6500-r_86106/
I have two of them with about 5000-6000mi on them and so far so good, BUT, before I used them I took them apart to look them over, they were pretty decent but one of them had way too much end play in the shaft so I had to shim that up, also one of them barely had any thermal paste under the module, that would have been short lived there. And one issue I had with both of them was that the mechanical advance wouldn't return all the way back at idle, at first I thought it was a linkage issue because it would idle too high but if I whacked the throttle a couple times idle would come down, but yet throttle was not sticking at all so I put the light on it and sure a hell the initial was 3*-4* higher than I originally set it at, popped the cap off and touched the weights and it snapped back, the weights are cheap **** stampings but with some detailing on them so far they seem to be working ok, oh and I don't go over .045 on plug gap, wider the gap the harder it is on the module and didn't really wanted to put them to the test, lol.. Anyhow, that's my experience with them, but I'm also a magnet for **** if there's a bad one in the pile guess who gets it, if you want to weed out the junk just sell me something, lol...