are late 944 hubs the same as the early ones

[pantswagen]

and do they fit a type 1 arm?
where can i buy - just the rear caliper mount
if this does fit together do i then need 86 only discs?

thank - you pleez

No, the hubs are not the same.
You'll just have to search around for the mounts (eBay, yards, etc.).
I'd have to know your set up to answer the last question.*

*if you refer to the rear turbo discs, then yes '86 only