Auto Ordnance 1911a1 Serial Numbers

I am trying to find the modal of my dad's Auto Ordnance 1911 .45 Auto.
It is parkerized and looks like the standard GI type 1911
Takes single stack mags.
All it says on left side of slide is:
An outline of a bullet w/ Thompson inside of it.
Right next to that, it reads:
Auto-Ordnance Corp.
.45 Caliber Automatic
Right side of lower has:
Auto Ordnance Corp
West Hurley, N.Y.
AOC33--6
The dashes are actually numbers but for privacy I'll leave those out.
There are no other marking anywhere to be found.
He has no idea how old it is so I was hoping somebody here could help.
We just want to know if there is actually a model and about when it was made.
Thanks in advance.