[mlin]

The hammer was definitely from a Ithaca 1911A1. The slide stop looks checkered to me, which is correct for Colt in that SN# range. Can you check the underside of the barrel? It should have some marking G, N, F & or something else.

If you want to retain the original grip bushing, you can try red Loctite. If the bushing is stuck with the grip panels, try using extractor like this.

1911 Grip Bushing Tool. the Galloway 10 - Etsy

This Tools item by CampbellsAttic has 3 favorites from Etsy shoppers. Ships from Dallas, GA. Listed on Feb 25, 2023

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[mlin]

7 marked barrel is proper for the Colt from that period per the Clawson's book.

Your slide looks to be period correct too. Here is my SN# 1635xxx for comparison that have the exact Pony style rollmark on the slide as yours.

 

[mlin]

Try any standard grip bushings first. If the hole was enlarged. try oversized bushings.

1911 AUTO OVERSIZED STOCK BUSHINGS & TAP

1911 AUTO OVERSIZED STOCK BUSHINGS & TAP https://www.brownells.com/gun-parts/handgun-parts/handgun-grips-parts/1911-auto-oversized-stock-bushings--tap/

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