Tried joining and asking questions on the SA section of the 31 club? Pretty good bunch of people, pretty helpfull to. As for rims 31's are 4 stud, so most 32 rims etc wont suit. From what i can see, drifteks are a popular choice on 31's atm.
Know of someone that may be selling their 4 door rb30de+t all legal and mod plated too. Know also of a white 31 turbo for sale also, 4 door. THink hes asking bout 7 though..
Theres few 31 club members that come on here, hopefully they could help ya out a bit too.