The No. 0 Grade doesn't appear on the 1906 price list. It first appears in the 1907 Three-Barrel Gun Co. catalog where it is offered with either Damascus or steel barrels.
No. 0 Grade, 1907 catalog.jpeg
By the 1908 Three-Barrel Gun Co. catalog it is only offered with Crescent Steel barrels.
Give me the serial number and I can look it up for you today in the copy of the records I have. Tomorrow I'm leaving for Minnesota so it could be a while before I look it up.