Back in the late '70's I owned an Ithaca/SKB Model 400 12-ga. 26" SK/SK, SST, PG, beavertail, 14" LOP to a factory pad, I purchased it from a private individual that also had the same gun in a 20-ga. version. My 12-ga. and the other 20-ga. gun I mentioned had satin oil finishes with much fancier figured stocks than the linked Mitsui gun's wood and hi-gloss finish.
These indeed are scarce guns. There may have been some Model 400's choked something other than SK/SK--but I've never seen one. There were also a few Model 480's imported, these of course were furnished with straight grips.
