Good question !
I guess that if you also change the axles (and probably brakes) the mountings between strida2 and 3 are the same.
But I always thought the wheels / bearings / brakes were better on the Strida 1 & 2 as they came from a motorcycle wheel manufacturer :
BERNARDI MOZZI MOTOR SRL
VIA G GARIBALDI 29
ZOLA PREDOSA
BOLOGNA
40069
ITALY.
I guess as they are in italy it might be easier to have a machine shop convert the cone and cup bearings into cartridge bearings - on the same axles, to keep the same brakes. There are myriad of cartridge bearings to choose from, so it just depends on the skill of the shop, to match the outside diameter of a cartridge bearing to the matching space / housing in the wheels, possibly making up a spacer to match the inner diameter of the bearing to the axles.
Also it will need a spacer between the bearings (as on roller blade wheels).
I think the rear pulley fo Strida1 & 2 is now ‘unobatainium’ and they wear most on the inside brake side … so if you can manage on the (powerful) front break only … the rear pulley should then last a lifetime.
There again you could just get a new Strida LT, and ebay the Mk2 
and benefit from 10+ years of development.
Good luck and please let us all know how you get on.