Given the appearance, caliber, and grips, it looks like a Police Positive or Police Positive Special. But the serial number ranges for those models don't match, in fact the number/patent date doesn't match for any model I can find information on.
The ejector rod end doesn't look like any I've ever seen on a Colt. I wonder it this was a "lunch bucket special" by someone working in the factory?
Sorry, not much help