Not easy. 700 with manual and being a wagon AND no rust?
sounds like finding a vintage coin on Times Square.
these cars are old and most of them are pretty worn out, inside&outside, body and engine, tired, rusted, clunked, junked, trashed.
Would building one be an option for you?
Luckily states of Washington and Oregon are big "Volvo states" so you'll have great chance to find one running survivor there. Dont expect one pop up too early in your neighborhood. Especially not the one you'd really need.
A simple search revealed a good start:
https://seattle.craigslist.org/kit/p...540851649.html
Good luck finding your diesel then start posting your projects on here.