I spent some time in the bearing industry in NZ, and those numbers are just a little unusual so that the national bearing merchants (such as CBC Motion) might not carry them, but it'd be worth a query.
It's become common for 'special' bearings such as these to be used by OEMs, like a 6205-16 which is a standard metric 25 mm bore bearing with a 1" bore. Nissan have several bearings in their gearboxes which have non-standard bores (one has a bore of 28 mm if I remember right), afterall parts is where the OEMs make their money.
As for the one with the integrated seal, the 32006JRRS, I never liked the built in seal used on taper roller bearings. Timken introduced it years ago to cut one piece from a wheel bearing set (generic outer bearing, inner bearing and seal became Timken inner bearing and special outer bearing ). But they weren't the answer to sealing problems, and bearing sealing has improved over the years.
You'll probably have to use one of the motorbike specific parts channels, like Honda or David Silver.
