I got this I-26M on a Zorki 4. No engravings of DOF and no meter scale is engraved. Only the aperture values are there. I have never found a lens where the engravings are missing. But I have seen some where the distance scale is engraved like the aperture scale (1.4,2,2.8 and so on).
This lens made for enlarger. It should only have aperture, but no focus adjustment. It is not factory error, but purposely made this way. I'm not sure in what type of enlargers it was used. You may find few variation of such lens with only aperture ring colored in black, or totally white. This lens is not common, but not rare ether. Usually someone has it for sale on eBay at any giving time.