I stumbled upon a price comparison service for registering and renewing domains, including new GTLD. It was relevant before, but I am unable to locate it now. Perhaps someone uses a similar service and can recommend it here.

You can test out the following:
- https://tld-list.com/
- https://www.domcomp.com/

Here are a few more:
topdomain.com.ua
https://domains.4it.me
tldes.com
price.co.ua