AIA indicates 1911 for the year.
.....some things about your anvil not in AIA. That was the second style of Trenton logo stamp that CF&I used in production. Both HB and CF&I had contracts with Sears to brand ACME anvils for sale. But Trenton had a vastly larger contract, and there are far more Trenton Acme's out there vs. HB Acme's. Also notice the oddly shaped "9" character in the serial number. There was a narrow range of Trenton serial numbers that used this character, roughly 30,000 anvils from what I can document so far.