Success, of a sort. The planer is built like a tank and I'm very pleased that just changing the bearings has probably given it another umpteen years of abuse.
The "of a sort" bit is that:
A) that blind needle bearing was a complete ******* to get out. I don't have a Dremel, so in the end I had a tantrum and drilled it out from the other side. Don't judge me. It still took a lot of bashing with a large hammer. Rotten design flaw IMO.
B) after a brilliant road test, engine purring, munching through oak etc etc, I noticed that the actual sole is slightly warped. Set for a light cut it isn't too horrible, but any deeper and it's way out of true. I'll come back to that next year.
The takeaway is that when Black and Decker tell you that bearings are obsolete, just give SimplyBearings a call. A joy to talk to and all was delivered the following day by the GPO. For completeness, they sold me NTN 6001JRXLLB/5K, NTN 6202ZZ/5K, SKF 6082Z and an HK1010 all for £24 inc vat and postage. Much less than the spare parts dealers wanted.
If this machine wasnt so well built, I probably wouldn't have bothered, especially as I am a dunce mechanically, so thanks to all of you for your comments! Definitely worth saving it from recycling.
Look at this - original (heavy n solid) tin case in mint condition and original blades in original pack (found in sandpaper box) I think I thought that if they came free, they were probably rubbish...
PS made in Italy. Never noticed that.