I doubt this is an original 1911- after aprox Ithaca added the set screw at the rear area of the forearm, and the fotos show this set screw- of course, the forearm on the gun as shown may be a replacement, and not origianl to the gun. A serial number check in Walt Snyder's Ithaca reference book would clarify this- nice looking Flues, regardless of gauge.

"The field is the touchstone of the man"..