I think you mean colt 1911A1 which was the US Military handgun from 1911 to about 1985.
Colt 1911-A1
Proofhouse.com has Colt sn data.
Made in 1945 in Ithaca for Colt.
You must call Colt to find out.
it was modified................
You can call Colt or visit their website which has sn data.
50-550 usd
The Colt 1911 A1 is rated at 395 FPS (Feet Per Second)
1968
100-600 USD or so
The A1 wasn't issued till after 1924 I believe..
I would contact Colt customer service directly and they should have the info you seek.