Good afternoon, this might be of some help to you.
The rear hub bearing on a sprint is Timken part 2585 / 2523S. These are about £120 plus VAT each. However, Timken part 2585 / 2523 is only £35 plus VAT and has identical dimensions. I spoke to Timken (who were very helpful) and they confirmed the difference is an increase of 0.2mm on the edge radius of the cup. They were even kind enough to send me drawings for both bearings.
It is possible that the smaller radius could sit on the fillet in the hub and therefore stop the cup pushing fully home against the shoulder, so I ground a whisker of the edge and it pressed in with no issues. The pictures below explain it better. The first picture is the cup as standard and the second picture is after I have ground the edge.
I haven't run the car yet as I need to source a new half-shaft, but as soon as its back on the road I'll update the post - The bearing dimensions are identical so I don't foresee any issues.