Maybe you would be better off here to name your budget and your expetations so we can see if anyone here coulld help you. I have been known to work cheap but not that cheap.
I am thinking they must have a bunch of old Chevy Blocks and Heads to use. Cast Chevy head on a 427 makes no sense to me. Actually a 427 is not making much sense with 11.50-1 compression and claming it can can have timing reduced and drive it on the street. Not going to happen.
I am currently doing two completely different SB Strokers. One is a tried and proven combination for me of a 418 - 423 cu in version and the other is a 422 cu in version. Both are using alum heads and roller cams with Eagle Rods, BRC Pistons, Total Seal Rings, Canfield Alum heads and one should be a 530 hp at 10.30- 1 compression to burn 89 octane gas. Tried and proven. The other is 11.00-1 compresion using 92 octane gas with est 560 to 570 hp with .600 lift roller and that is also tried and proven.
I ahve done economical 383 but never an engine that I can sell for under 3,500 .
Maybe it is a good deal.Who knows.
Ed