Shot bearings

31trum your right tommy, sorry for being quick/brief, VB.
there are numbers on the bearing race/case for the external/ inner diameter,and width. plenty of places on-line to order from, and should only cost a few quid each, also, it's worth asking for stainless. i work in a printers and find they last much longer

Good point murtle maybe able to "up the spec" in other ways as well if you speak to someone at a bearing shop / suppliers.