There is +P rated at 125 gr/850 fps, and another at 158 gr/1200 fps. Neither will blow up a mechanically and metallurgically sound gun of this era, but hotter loads will accelerate wear. I would try a few +P loads (Speer Gold Dot, Hornady Critical Defense are two often recommended), see how they work for you and the sights. These will be fairly expensive and you wouldn't want to use them all the time.

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Alan
SWCA LM 2023, SWHF 220