what area are you in? i have noticed prices vary greatly due to geographic location.
For northern california where i live i think 7000 is steep for a 83 but without pictures that is speculation.
I have a 83 that is more built but probably not as clean and i would value it around 4500ish but that is with dual cases, 37's gear and lockers and a bunch of other work done to it.
for a stock shtreetable 83 that is relatively clean i would guess cheesemaker is right on in the 3-5k range.