I have a 158.1940 Kenmore that hubby bought me in 1976 when our daughter was 6 months old. She is as much a workhorse as ever. She is my back up girl, and can sew on anything including vinyl, leather, upholstery, jeans, etc. The Kenmore's of the 1970's were the last metal gear machines, then they went to plastic to make them lighter and to make sure you would buy another machine when the plastic ones wore out. Clean your 1752, oil her, and enjoy her.
I have to say that I am very lucky---I own 4 of the 6 sewing machines I have always wanted--- The 1940 Kenmore,
the Viking 500, the 1948 Featherweight, the Viking Mega Quilter---the only 2 I am missing are a Brother embroidery
machine and a Singer treadle. Maybe some day, but for now I am content.