It's not uncommon to see fixtures like these repainted and restored, but the ones I have in my album were actually painted light grey by the factories. Probably very rare anywhere else, found only in this part of PA.

The Westinghouse OV-15 & OV-25 were available in light grey from 1964-1978

The McGraw Edison Unistyle 175 & Unistyle 400 were available in light grey from 1967-1975

Its the same for McGraw Edision Unidoors, I saw some pictures of them grey but I haven't actually seen them grey in person.....but they do come in grey also

Yep, those also came with the same option from 1971-1980. These Unidoors are very rare and weren't as popular as the Unistyles.

I've actually seen light grey Unidoors (with the deep bowl refractors) in Canada on the 405.

Of the luminaires you all have discussed, the only "factory" grey fixtures (aside from GE and AE) I have seen are Unidoor 175s. The Los Angeles area has some OV-15s, OV-25s and Unistyle 175s and 400s that were painted grey. They were actually rebuilt by a company somewhere in the LA area and refitted to HPS. Some are "empty" fixtures designed to operate on underground series circuits. The transformers are underground next to the poles, and the luminaires only have connection terminals and ignitors!