George Milton at Quality Light Metric did a wonderful job rewiring my Weston Ranger9 for modern batteries and calibrating it. You won't go wrong using QLM.
That said, Richard Ritter repaired and calibrated 2 Pentax Spotmeter V for me. Excellent quality, service and at a reasonable price. I figured his connection with Zone VI Studios made him the obvious choice for a Pentax meter.
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