Having had a rattly fan pulley on my sprint, and being unable to source a new replacement, i managed to find the following bearing. I've only done a couple of hundred miles since, but it seems to be doing the job.
It came from Henderson Bearings, and is part FPS61.
I daresay it's just Chinese tat, but I'm sure cross referencing may allow someone to find a good quality one.
All that was needed was to chop an end off, and shorten the other.
I dismantled mine to see if the bearings were seperate from the shaft but they are not, the shaft forms the inner race. Although if needed a new shaft could be made with an interferance fit to the new bearins,
But could to see you were able to find something suitable.