It's a Garrett Airesearch product. They make many turbos both as an OEM supplier and for the aftermarket.
It's a TE model I think, a number of TE configurations were sold for automotive use. This particular one looks pretty small, for a smaller engine.It looks like an older item too (maybe from the 1980's?), because Garrett dropped the AiResearch name at least 10 years ago.
Look through their website or contact them for more info.
http://www.turbobygarrett.com/