I seem to be getting here too late to answer most questions. 
Yeah as Mark was saying, the MR85 bearing is easy to get a hold of. I bought a ten pack of them at ABEC 5 rating for $10 from Aliexpress.
I was concerned that being such a thin bearing it would lack durability/longevity. This doesnt seem to be the case, the original factory bearing in mine is still performing perfectly with zero maintenance. I haven’t touched it and it came unlubed.
This is one cool aspect of the design. None of this opening up and cramming it with thick lube or grease every month to keep it responsive. The set up just works.