If the code is the same, so the bearings should be also.
North America, a reasonably large user of bearings, is still imperial for much of its industrial kit (stuff in use presently, rather than brand new, for the latter I don't know), so imperial bearings are available. So find a NA bearing supplier and look up the code on their site, and see if what specs they quote match with the UK/EU supplier you have already found.
It's also worth taking a bit of time to understand the letter suffixes too. For example, there are high-temperature bearings designed for use inside engines, where the bearing only achieves the correct tolerances _after_ it has got pretty hot (otherwise it has excessive play). You probably don't want those in a woodworking machine, unless they are explicitly specified by the manufacturer!
That's a bit annoying, in that classic motorbikes in particular are a market for imperial bearings, but I suspect probably only the high-temp type.
But... at a guess, the bigger the imperial bearing is, the more likely replacements can be had, on the basis that smaller kit is likely to have "gone metric" a long time back. Worst case you might need to source in the USA and take a deep breath before shelling out for the cost - but you should get them.
All my kit is metric presently, but I usually replace the chinesium ones with SKF oil-sealed ones, partly for quality and partly for ease of cleaning - there is negligible risk of forcing sawdust and other stuff into the ball races. Given the size of machine, the bearings on my Kity's planer block are huge, and show no sign of play, although it's probably at least third-hand.
In my very limited and amateur experience with both belts and bearings you need to 'turn detective' before ordering. Hope you find what you need.
E.
