1920's Team Ball Find

[azbob]

Help. I found this baseball in a box of old stuff going through my mother’s estate. A local AZ dealer suggested Net54 as a good place to start my info hunt (I'm new to all of this). It’s in pretty rough shape (see photos) but I can read “George H. Sisler, worlds hitting record” fairly clearly and there are multiple other signatures and many scuffed too badly to read. There also appears to be a date but I can’t make it out clearly. I’m assuming it’s a team ball from the early 20’s and I do know that my grandfather was a baseball enthusiast and pitched in the III League during that time.

I’m trying to figure out what team this is, what it might be worth, how to “authenticate” it, and how to keep it from getting any more “worn out”. Also, are there such things as conservators that might bring this thing back to a better condition? I’m not a collector or trader by any means and don’t really know if I have a rare find here or not. Any suggestions or input would be appreciated.