That's a short action stock with HS floormetal and 10 round mag, first gen I think judging from mag.
Also looks to be the standard HS 1 inch thick recoil pad for the adj LOP version and yes they look that thick.
Do not confuse this with the M24 recoil pad, it is a Remington 1/2 inch pad and of course a long action stock, PST024 is the part number.