Moonpie, search for "Sterlingworth Co." or "Sterlingworth pin gun" on an internet auction site (GunBroker) and get an idea of asking and sold for prices for your gun. Or check Roy Eckrose's auction results archived on the main page this site. I didn't check your serial but assume it's the so-called model 1911 as marked on the forend iron? I gave 400$ for mine but have seen asking prices north of 1K$. Retained condition probably has more bearing on price than relative rarity.

jack