It is pretty unusual for a Kenmore model to span model years. Only thing I can figure is that after 1971, the model 1516 was no longer manufactured. A few years later, Kenmore must have figured they had a winner and "reintroduced" it in 1977. I don't know the true answer, but I actually think…
Kenmore Vintage Original Collectible Sewing Machines for sale
Restoration of a 1975 Vintage Kenmore Model 158.1730 – Professionally Restored Vintage Fine Quality Sewing Machines
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eSheep Designs: Love My Vintage Sewing Machine
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Kenmore Collectible Sewing Machines for sale
1970's Sewing Machine Review & Tutorial - Sears Kenmore 158.17550
1970's Sewing Machine Review & Tutorial - Sears Kenmore 158.17550
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Vintage Kenmore Sewing Machine
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