They are standard size housings, I can tell you that much. the 42 or .42 is the A/R of the front housing and the 0.48 is the rear. the "14411-05U20" is a nissan part number, so they are a nissan turbo, and given the housings sizes are standard I would say they are stock. It's possible they have been rebuilt, and perhaps given steel wheels, but also possible they were just removed for some other reason and re-fitted at some point.