Scott,
I agree with Jim's comments. A bat with a mis-matched number would generally bring substantially less than one with the correct player's uniform number or even no number at all. From my end, I am more interested in whether or not a particular player actually used a bat as opposed to whose name is on the barrel. I think that is becoming the prevailing view in the hobby. That having been said, there still is substantial interest in 1950s-60s HOF players bats even with mis-matched numbers. For many it is a less expensive alternative to getting a HOF palyers bat with all matching use characteristics.

In terms of the X on the knob, it could mean several things. I don't believe that you mentioned whether or not the bat was cracked. However, I have spoken with one batboy from the late 60s and early 70s who indicated that it was common practice to either blacken the knob out or place an X on the knob once a bat was cracked to identify as being cracked so it would not errantly be brought to the plate again.

Hope that helps...good luck with the Aparicio bat!

Regards,
Andy
www.vintagebats.com