Looking up the branding I've managed to find out that they are Rigida rims (now Ryde) Zac 2000's - it said
https://www.chickencyclekit.co.uk/ are distributors but I can't find anyone selling them. Worth knowing if I fancy replacing like for like
You can buy Zac 2000 rims (current ones - no idea if there have been changes) at Taylor Wheels - despite the name they are german.
https://www.taylor-wheels.com/
They also do complete builds with Zac 2000s.
I bought a pair of Zac19 complete wheels from Taylor wheels with quality Deore hubs.
Came out at about £100.
Good company - I can recommend them.
A pity that despite their varying builds they never seem to use Sputnik rims. No idea why not.
I agree with your idea of buying wheels where, if you like the set-up, hubs and rims, you can just replace the rims when needed - I have the idea that many folk just chuck the lot when the rims wear through or run the hubs into the ground without maintaining them.