pf2e.fyi
From Pathfinder Guns & Gears, which isn't enabled.

Reinforced Stock

ITEM 0
ATTACHED-TO-CROSSBOW-OR-FIREARMFINESSETWO-HAND-D8
Price 2 sp
Usage held in 1 hand
Bulk L
Category martial
Group club
Damage 1d4 bludgeoning

A reinforced stock is a weighted crossbow, firearm haft, or grip customized for striking in melee.

Pathfinder Guns & GearsORC