340 High Compression Pistons

Jegs has those FHR pistons for the small blocks...

United Engine Machine IC9975.040: Chrysler 340ci FHR Forged Pistons Flat Top 2V | JEGS

I believe you are looking for 4.080

https://www.uempistons.com/catalogs/icon_catalog.pdf

on page 68 of catalog......piston weight 606 pin weight 118 grams