You can't fit a 'mk2' door mirror to a 'mk1' - you would have to bolt it through the quarter light glass!!.
On a pre '84' car the door mirrors bolted to the door skin under the quarterlight. On 'mk2's the quarterlight was deleted, the window and forward runner changed and the mirror fitted within the window aperture where the q/light 'used to be'.
The early ones a rather like an old type wing mirror - but fitted to the door.
If you can't find a Volvo one any half decent car accessory shop should be able to find something to fit.