I have KYB gas-a-justs on the back of my Amazon and they are HARD. Even with 4 in the car they are still hard. Don't know what the fronts are, they are grey and anonymous, but still work reasonably well. I'd probably go for Konis set pretty soft but they are expensive so will likely buy the Monroes that Brookhouse, the main UK classic Volvo parts supplier, lists as the standard option.
Poly bushing the front inner upper bushes to replace the rubber cotton reels isn't a bad idea. Current replacement rubber ones apparently range from poor to bad as far as life goes, not as good as the old ones anyway.