I'm doing a 5.9 build and just got these. I'm using the MP R/T head. Should be around 9.2-9.5 CR and I can run pump gas. [URL]https://www.ebay.com/itm/174387756580[/URL]
Those look like direct replacement pistons from Seal Power. Nice price for a piston and ring set up. The overbore size adds a minor increase in compression. Coated skirts for a nice plus too!