Welcome to TFF.
You have a .38 S&W caliber 3rd model made 1911 in Fitchburg, MA.
The plastic grip plate shown is an old Franzite or other aftermarket grip, which would hurt value to a collector, and these are not much sought after by shooters as the ammo is semi-obsolete, so value maybe $100 plus or minus.
To satisfy my curiosity, what's written on the folded paper note between the grip and mainspring?