What is your definition of "unmolested" ?

I was thinking of a car that is nearly 100% original mechanically. In my mind, a 40+ year old car that is completely original has either been in storage for a significant period of time, or was parked at some point in its life with the odd mechanical issue that the owner did not elect to repair due to an unwillingness to replace parts that were no longer available from Volvo or the OEM.

I think that this hypothetical car would actually be worth less to most buyers than one which has been driven on a regular basis throughout its life, and has possibly had the engine and/or drivetrain rebuilt, or a few aftermarket parts installed, to keep it in a roadworthy condition.

If this sounds like your friend's car, then it is really 'nothing special' in terms of its value on the market and would probably sell for $2-$2.5K. If you fixed the floorpan rust and splashed on a fresh coat of paint - and provided that the body is straight - you might get between three and four grand. 122's that command more than $5K are either restored or modified for performance use (e.g. B20 with cam, exhaust, suspension mods, disc brakes and so forth).