I seem to recall that full cloth was an option, with the default (i.e. 'Nothing extra to pay, sir') being cloth centres and vinyl sides. (Which is actually the most sensible arrangement as the vinyl is harder-wearing than the cloth, and lasts longer than the leather, but that's by-the-by.)
I think that porsche logo cloth was a cost extra (as in, you paid more for it.)
Cloth door cards (as opposed to vinyl) was another cost extra (but may have been included as 'standard' for certain models of cars; I don't think I have ever seen an S2 or Turbo without it).
Then there was the 'leather' option, which is really leather fronts to the front seats and vinyl everywhere else. And the very, very rare 'full leather' - which was leather everywhere (including on the dashboard I think), and cost about £4500 extra when the car was new.
And then you throw the sports seats vs. 'comfort' seats issue into the mix.
NOTE - I could be wrong on a lot of this; it's working from memory of bits I have picked up over the years.
Oli.
ETA: To the OP: The best advice when choosing a 944 is to choose the best one you can find, and not to worry about colour or interior. A really good car in a colour you are not that fond of is a much better bet than a ropey example with your perfect colour and interior. And bear in mind that the interior can be very easily changed as well - I put leather sports sets in mine and sold the old cloth comfort seats, and it cost me less than a hundred quid all in.