Just my thoughts and experiences with the HK USP 9mm Compact.
HECKLER & KOCH USP COMPACT .40 - Athlon Outdoors
TALON GRIPS for Heckler & Koch USP Compact 9mm/.40 : Sports & Outdoors
HK-USP Metal Model Universal Self-loading Pistol 1:2.05 Scale - ToyGunMarket Online Store
The HK USP Compact 9mm: A True Classic! - The Mag Life
Accessibility Tools
New to me USPc 9 low serial number?
Umarex H&K USP Compact Tactical GBB Pistol Model: UMAREX-GBB-USPC-TAC $141.50 - - Airsoft Store Products
H&K USP Compact V1 9mm - ADELBRIDGE & CO