another possibility (for both the "Olmo" above and the OP's) might be Romani. This is a popular fall-back because Romani did A LOT of contract-building for many brands as well as shop and house-brands, were very active in the era represented (short DOs but still nutted brakes and both types of cable-routing) and they liked those fluted stay caps, those pierced lugs and that style forkcrown, but really would build to order so their style clues are varied. They could do something very nicely finished with ample chrome, or more plain-jane. They also didn't mark them in any way, usually not even serial numbered.

When in doubt, think "Romani".