I can't find anything on the numbers for that exact combo either. It would be interesting to look at the door tag and decode what sales distict it came from. I bet not up north.
Yes RWdefrost was an option (although is was standard along with the million mile odoometer in NY only).
The numbers aren't published on option breakdowns for fox bodies. However, you can go to Stu's site and get something pretty close, as he has those numbers from an actual Ford database.
Does your car have the power driver's seat? If so, mine is optioned exactly like yours, except mine is teal.
Going from the number of repros I have done, the most unusual omitted option is the power driver's seat. Otherwise, your combo is pretty common (at least as common as a low production 93 Cobra can be )