Well I just changed from the same wheels and tyres as you as they were a bit lardy. Its a little bit above your budget but I got hope pro 2s on stans arch rims. Running them tubeless with Bonty tyres (500g and 570g) I think xr on the back and acx on the front. The sidewalls look a bit flimsy for some stuff but I have some tubeless ready ones coming in the post.
Anyway I got these from just riding along. They are well built and were fairly quick too. The wheels are much lighter than the on ones. I worked out I saved around 3 pounds on wheels and tyres.
I rode them at the HONC and they felt great, changed the feel of the bike for the better and despite my usual clumsy riding, no punctures 🙂