It's realy, really hard to tell without pictures.
Smooth grips, from what I know, are not original to the gun.
Is there no date stamp at the top front of the receiver? If not, it's probably a 1920 Commercial. If it's in 85% condition, with similar condition strawed parts, and all matching parts (except mag) then it's probably worth somewhere in the neighborhood of about $500 to $800. Maybe more. They sometimes go for more on GunBroker but not always.
But that's all mere speculation without photos...
Do you want it? Does it speak to you? I've seen people pay more for guns than they should have but were still glad to do so. They all go up in value so one day it'll be worth what you have into it...
