I Google everything. I have a 158 also in the cabinet. Weighs about 40 pounds, right? There was one on E-Bay and the current price at the time was 168.00 I couldn't find a year on it though. I am thinking 50 -60's.
Anyways, like you, I didn't have a manual either, so I just Googled: "Sears Kenmore Sewing Manual". Let me know if this works for you, because I got a website that seemed to have ALL kinds of manuals for sewing machines!!
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