I have a Gulbransen upright and it also has the Gulbransen name cast
into the piano plate.  However, I know it was not made by Gulbransen,
because in the lower left corner of the plate there is some very faded
writing that says "quality piano plate manufactured by the ???? piano
plate Co."  Like I said, it is very faded and I cannot make out the
name of the company.  I hope this helps.

Benjamin Haass