Post and beam auger

I picked up a post and beam auger with a 2″ bit from a retiring shop teacher who had it sitting on his desk for 20 years.  I had to drive an hour to get it but the low price and not having to pay shipping justified the car ride.  It’s not a familiar type such as a Millers Falls model and in fact I’m not sure what brand it is.  If anybody knows the manufacturer or can tell me anything about it from the pictures I would appreciate a quick comment or email to clue me in.  Some of the mortises I’ll be cutting will be 2″ wide so this contraption should speed that along.  I’d really like to find a 1-1/2″ bit to drill the rest of the mortises so I’ll have to keep my eye out for one of those.