I belong to a Kenmore group and the spreadsheet says this model was made in Taiwan and was sold by Sears from 1983-1987. Price at those times ranged from 159.99 to 225.99. Should be a good one.
If you are getting gobs underneath, then rethread the entire machine, including the bobbin. Something may not have caught right. This usually will solve those problems, and it may happen again. Also, make sure the bobbin area is clean and free of lint.