My grandpa had some connections to the Rockets and gave me a ball signed by these 4 as a Christmas present when I was a child. Would love to hold on to it but looking at some crazy medical expenses for my wife coming in the next year.

Any ideas to figure out how much this ball would be worth? Anyone here potentially interested?

I can add some pics. The balls has been in a protective display case for probably 10-15 years without being touched. Signatures still look great

Sorry about your wife's medical issues.
There are some posters who know more about this stuff than I do, but I think your best bet is to get it authenticated. otherwise I'm not sure you'll be able to get a whole lot for it.

With it not being an authentic game ball, and as mentioned the authentication issue for the signatures the ball is likely worth more to you sentimentally then you'll get for it by selling it.