It looks like a knockoff singer electric on top. Probably a K-Mart or Sears. I could be wrong as there are so many singer models out there. Not that those are bad per se, but parts aren't always interchangeable with singer.

I have the legs from one of those to tables attached to an old door to make a big table. I used a 1x8 to brace it underneath.

If you look at thrift stores you can find sewing machine tables where the sewing machine folds in and it just looks like a normal table. There worth $10-$20 if it has the pedal. Don't buy a sewing machine without the pedal because they cost as much as a good used sewing machine with one.