My friend is selling some Houston Rockets related items, check them out at the link below, all are professionally authenticated. https://m.ebay.com/seller?sid=csk.5vhshne&nav=MYEBAY
I have been told that the above link does not work, try this link out for the Yao basketball and other items: https://m.ebay.com/itm/YAO-MING-HOUSTON-ROCKETS-AUTOGRAPH-BASKETBALL-BECKETT-COA-/132501070642