Marco,
You should all know that today is OZ day, the day Mr. Cook lost his way and discovered Australia!! And that the best of our forefathers came from the worst of English jails.

I have just had a look at the circuit diagrams for the SP10 and I must admit I did not realize they were so extensive. It would seem that the control circuitry should certainly be capable of decent control of the motor/platter and it does have more coils on the stator which would potentially enable more smooth rotation.
However I would venture to sugest that the SL1200 series does have a more refined control circuitry than the SP10.

I cannot see from a copy of the manual that I have, exactly what form the bearing takes.
It does look as though a replacement could be possible but I would have to get hold of the actual motor assembly myself.
If there is anyone out there that has an old and useless SP10 or one which does have just a defunct bearing, I would be happy to further investigate the possibility of perhaps producing a replacement bearing for the SP10 if there are enough takers.

However looking at the considerable amount of discreet circuitry on the four or five PCBs would make me aware, as Marco indicated that a lot of the caps would possibly need replacement.
It is not difficult to see that the genesis of the SL1200s lay in the SP10 design.
Excepting that the SL1200s were produced with mass production in mind at a much lower retail cost.