Here is what MusicDirect says, and for the Inverted Bearings
I've used Super Lube Grease for many things with various hobbies besides audio. Easy to find, reasonably priced are two plusses.
As for non-inverted VPI Bearings, and viscosity requirements, I don't see how anyone can use a grease with these bearings, as seating the bearing shaft into the well will be near impossible.
Also, any excesses of lube oil or too thick Lubes of either oli or grease will merely be "scrubbed off" as the bearing shaft seats, and will pool out onto on the top flange of the bearing well. Been there, done that.
Probably another rule of thumb is "That if a little is good, more is better" is not true with Platter Bearings. Using the correct amounts of lubrication is important.