Welcome to Mud!
looks to me like a generic cheap vise. Does not look very robust or desirable, from here (sorry). From Japan likely when they were still doing cheap tools before Taiwan and then China. I have some of their tools like that, not real bad but not great either and no manufacturer markings. I imagine you won't find specific parts or be able to identify the manufacturer. But then there is probably no need to. If still functional, just add a couple of bolts to hold it down with or without swivel and use it for abusive work if you want to save a better vise; or use as long as you can if it's your only one until you can get a better one. If not functional, I would not put much money or effort in it.
added: since I sounded a bit negative up there, to be fair I should clarify that for me the main design issues would be the flat guide bar which can be bent (seen several) and the exposed screw which if not kept clean of metal filings and shavings may wear out faster than it would if protected.