I bought my 91 318i brand new, and it didn't come with floor mats. I have gray door panels, gray carpet (schiefer [slate in German]), and had gray cloth seats (since swapped for black leatherette). I reused some BMW gray rubber mats that came from a Euro 84 318i.
If you want some more detailed information on your option codes, sign up on bimmmerforums.com, enable private messaging and/or e-mail contact, and locate a VIN decode thread in the 3-series E30 forum. Follow the instructions in the first post in the VIN decode thread. The eventual reply will be a fun read, and perhaps you'll get the answer to your mats question.
With the other two BMWs in the family stable, I've seen tan mats on tan carpet, and black mats on gray carpet. Happy hunting.
Adios for now,
RM