Need help with rim size and offset

Hey guys wondering if anyone can help me out.

I’m looking for new rims and need help with offset. I want nice sunken wheels that are flush with the body. The front is stock (91 240sx) but the rear is 30mm wider on each side. I want a 8 inch wide wheel in the front with a 9.5-10 in the rear…any help would be appreciated.

Also if anyone can get rims please PM me.