Belinda,
For all I know, the Monroes may be what Volvo sells for PVs, but made in Belgium. I have no idea about the Delcos. Basically my notion is that, if a PV is used for normal street and touring use - not racing or rallying - it doesn't really need any hot-shot shocks: the cars are so light. This, however, is a personal opinion, and others may have a different one, and justifiably so. BTW, I'm not being conservative out of principle - I have ipd bars on my car and like them: many others will argue that's over-kill. I have a sneaky suspiscion that the shocks I found on my "62 PV544 when I got it where the original ones. The dust covers were completely rusted away and the rubber bushings were practically rotted to pulp, but the hydraulic part was still perfectly functional and not leaking.
Bob S.