Tricky.
Lots of cars are made in a year, but very few get kitted - you tend to see only the most desireable vehicles from the biggest names. Muscle cars. Italian exotics. That sort of thing. The only mainstream, injection Volvo kit I can think of off the top of my head is the early 90's 850 estate, from when they were dominating touring car races.
*BUT*
If you're willing to go off the beaten path, and put in some work, it may be possible. 1/43 is a popular (outside the mainstream) scale for cars. It's one of the main scales for die casts, and for the auto modelling equivalent of limited run/cottage manufacturers (ie. if Classic Airframes did cars, they'd be in 1/43). Doing a bit of digging, it seems that 'Arena' has just started releasing a series of
Volvo 142 rally kits. They
should be pretty decent- resin bodies, PE details - and a good basis for converting to a road car. You'd probably need to replace the interior, and possibly the rims, but it's probably the best start you're going to find. And depending on the time/money/effort you want to put in to the project, there's also a resin model (think die cast... but resin) of a
Volvo 145, which you can probably rob the interior and wheels from.
The Hillman is a little more straightforward.
Somerville Models do a white metal kit of a Minx Saloon. May not be the right year, may need some trim changes, but hopefully it's close. Barring that, there's a
few other die cast optionsthat you could look at - break them down, clean them up and rebuild them like any other white metal kit. You'll have to do some rummaging around Google (and eBay, I'd suggest) to see what there is, though.
Other than 1/43 die casts, resin kits and conversions though, you're going to be out of luck. There's nothing 1/24 and mainstream out there.