1960 Pirates Ball
 

I'm not an autograph guy, so asking for some opinions.

I have a friend that has a 1960 team signed ball with about 20 signatures. Sent to PSA, it came back as authentic except for the Murtaugh sig, which was labeled as clubhouse. Also, the ball includes Tommy Burgess who was a minor leaguer and not part of the 1960 team.
I saw one picture. The ball is white & clean with all signatures in blue ink, not faded and readable. Includes Clemente, Maz, Umbricht.

I would appreciate any thoughts on value.
Thanks,
John