Magic Johnson is all about the Balls ... so much that he says he's willing to shell out nearly $1,000 for both Lonzo AND LaMelo's signature sneakers!!

The Lakers Prez was leaving Craig's in WeHo when we asked him if he was gonna cop his prized rookie's $495 ZO2s ... or his H.S. phenom baby bro's $395 Melo Ball 1s.

Magic says he's coppin' BOTH ... and doesn't care how expensive BBB sets the price tag on their shoes, as long as Zo balls out for the Purple & Gold.