I have the same problem you have, mr Mike. Left my SKF catalogue when I left an offshore company,
but I still have the concepts of the item catalogue manual
I wrote for them, with some rolling element bearing information.
The info Phil gives indicate the bearing is a 1-row ball bearing. ZZ may be 2Z, indicating two steel grease retainer rings fixed to the outside ring keeping grease between the balls.
The indication 2RSR of FAG might indicate the same, but rubber rings.
The sizes 7/8 X 2 X 9/16 are than the ID(shaft) x OD x Width.
So ask your bearing supplier for a 1-row ball bearing that size with two grease retainer rings (either steel or rubber).