Bearing replacements are in this thread (including what to buy):
https://pinside.com/pinball/forum/topic/berry-400-vibratory-tumbler-bearing-replacement
The 626-ZZ ball bearings can be bought dirt cheap on ebay:
ebay.com link: 10 Pcs Premium 626ZZ ABEC1 Metal Shields Deep Groove Ball Bearing 6 x 19 x 6mm