What Firebrick said! Probably no S/N as may have been paper label which is long gone. Pre 1941. Looks like a good resto project. The CI guard alone is worth $200, has the table lift, and nice table, no arc of shame. The motor is probably not original, but looks period. Can change out motor to 1ph or use a VFD. Nice find and certainly worth the effort. Good place to start might be here: A Delta Curiosity: Keep us postedThat is a prewar delta 17" Many call them DP600 for the main casting number. Delta never called them by the "dp 600" however, just a 17" drill press.
Its prewar because of the cast iron front belt guard/art deco rear guard. During the war they went to an all pressed steel guard of similar styling, after the war they simplified it and got away from the art deco influences.