Yes, but if it's notchy then you have corrosion lines in the races, it probably also means the grease is holding water so it's likely just going to get worse.
I've done this as a stop-gap until I could get around to replacing them.
Bearings - find out what they are and search ebay for a quality brand of them.
Loads of good quality makes out there SKF, NTN, NSK, Timken, FAG, Koyo etc...
These are a good shop to use if you'd rather just go to an online shop
http://simplybearings.co.uk/