How about a pro bat that has all the characteristics via length, weight, type of wood, etc., as a well documented professional game bat, but for some reason there is no model number on the knob.

This is a bat from the 1950s-60s so technically there should be a model number stamped on the knob.

Seen any of these?

I asked Troy at MEARS/SCDA once about this and he said a bat like that basically slipped through quality control, and was likely counted in the bat order shipment records for a particular model.