They are the same size, but the shielding is different. Without doing a bunch of digging I suspect they’ll fit and probably work. I think yours have similar shielding to the bearings on my roller skates, optimized a bit more for low friction than good sealing. Bearings are pretty easy to clean if needed, but I would wonder about trying to actually get them out of the machine to clean them.
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Edit: After a bit more digging, ZZ refers to double shielded, 2RS is double sealed. Shielded keeps big chunks out, but dust will still get in, sealed is…well…sealed. Shields can be popped out for easy cleaning, but I would not want to regularly disassemble the thing to clean 53 bearings.
I have purchased bearings from FUSHI via their aliexpress store and they seem to be good, in spite of being quite affordable. I would buy from them again. Shipping was relatively fast, too (considering).
I agree that 2RS are a better choice for this application than ZZ:
For my MPCNC, I bought them from Adam, and of course they are good quality. I know that importing things inexpensively into Canada is an issue, though.