do 7-A-9 dated seatbelts work with an 02D car?

Yes, if they are standards. week 7 is around 3rd week of feb.

...I assume they are the originals then...the only ones left in the car are the upper roof mounted shoulder belts....I guess i know what date to search for for the remainders....I assume they would all be the same date??

I can not answer for a 69, but for a 67 they did not have to be the same date.

They do not need to be the same date. usually the fronts are one date, the rears another.

Usually the sets are the same date. The different sets may or may not all be the same date.

Set = rears, front laps, shoulders.
http://www.camaros.org/seatbelt.shtml