Missing are the cutter guard, support arm, arbor support, arbor, and I would bet the arbor driver. However, the two lock handles for locking the support arm in place are visible on top of the head. They are often missing. So you may find the other four parts lying around somewhere. And it is relatively unusual in that it does appear to still have all of the belt guards. Usually those are missing.
As best I can make out, it is an MFB. And I think that the serial number begins with 007, which agrees. There were 12 models of the mill made, M1, MF and MH through M1C, MFC and MHC. The M1 did not have power table feed. The MF did. And the MH had lever operated table lift and traverse.
Downloads has several versions of the Operating and Parts manual, with MMB5 probably being the preferred one. Access to Downloads requires Donor status.
Incidentally, I don't know why I never noticed it before but none of the parts manuals seem to show either the arbor or the arbor driver. Cleaned up Factory drawings in Downloads includes drawings of those, plus a lot of other lathe and mill parts.
None of the obvioously missing parts are show stoppers. If you do decide to pursue it, I would carry with me a printout of MMB5, an oil can and some grease and after confirming that it is bolted to that abysmal stand and not welded to it, lubricate everything before test running it. If you do buy it, leave the stand for the owner to deal with!