Here's one of Antoine Walker when he was traded back to Boston. He played in #88 for a couple of games IIRC before getting his #8 back from Al Jefferson who switched to #7.
In relation to KJ and his trade to Phoenix. It's weird seeing KJ and Nance in their new jerseys with different numbers. They switched to their customary #7 and #22 the following year.
Luckily, that's stopped in the NBA. I remember for years seeing K.Malone and J.Malone on the Jazz jerseys. I also believe M.Malone and J.Malone happened on the Bullets?
I think the NBA stopped doing that around 2003-04ish when Rasheed Wallace was traded to Detroit and teamed up with Big Ben.