I'm not sure that Komura and Osaka et. al ARE the same. D. O. Industries for one was the importer of Fujinon lenses in teh 1980's soem of them branded D.O. Industries. Komura was in the large format lens business for many years, well into the 1980's. They also made a wide variety of lenses. Thus, the mens in questionmay or may not be a 4 element lens. I can't speak specificallyto the lens you re considering but I can talk some about their 150 mm lenses. I know they made an f2.8 (I have seen it) and an f3.5 (I own one). Both of these are modern lenses that are multicoated.

I have tested the f3.5 multicoated lens side-by-side with a 150 mm Apo Symmar. Wide open the 3.5 gave a useable to acceptable image and stopped down to f22 it was sharp. The differences between it and the Symmar were in contrast rather than sharpness with the Symmar being marginally more contrasty.

It's likely a decent lens and if the price is right buy it. One more thing .. check the coverage carefully, make srue it has sufficient coverage to give you decent movement on yoru 5x7.

Ted