I'm working on (2) GMC 270 engines from WWII trucks and am having difficulty sourcing pistons & rings. These are the dome top pistons.

I found that EGGE has piston blanks that they can finish out to whatever oversize you need, from std. to +.100.
When I went to order them I found they no longer have rings to fit the pistons.....they previously had Grant or Hastings rings.

Called Hastings...discontinued.
Called Grant....no stock but are supposed to get back to me if they can make them. Their p/n P2791 or C2791 (chrome)

Hastings suggested I talk to Total Seal but wont' be able to call until next week.

Ideally I'm looking for a .020 oversize set for one engine and a .080 oversize set for the other.
Worse come to worse I could bore the first engine larger for whatever size I can find, and could sleeve the second engine back to a smaller size.

Any suggestions for other sources for pistons & rings?