I will keep looking though, you have peaked my curiosity.I see what you mean there. About the closet thing I found too.Looks almost like webbing stretcher pliers but the new ones offered today are different.
They could be very specific with the little detents in the jaws.I checked all my resources and do not see anything like them anywhere. The screws holding the ends on make me think they may be custom made for a particular manufacturing process. Osborne could have been contracted to make the pliers for a specific business.I will keep looking though, you have peaked my curiosity.
They are still in business here in NJ send them and email with a picture if nobody can ID them. Very cool indeed.
http://www.csosborne.com/