340 pistons

If financially feasible, I would cut the domes off to make it a true flattop. Those domes may have been cut down already. Yours look like something I had done years ago. That will bring compression down to a more reasonable level and save some weight. Speed Pro and TRW made some pretty heavy pistons. Couldn't hurt to take a little weight out underneath as well. Mopar use to sell similar units with their own P-# for 340s & 360s. I've seen all 3 brands "advertised" at anything from 11.5-1 to 13-1 with the full dome.

If you can't get a deal on machining, a different set might be worth considering.