Really sorry to hear about Willows accident - it sounded awful. Completely understand you’d rather stay away from barred cages now. Wonderful that you’re wanting to get another hamster
Dreamtree has given good tank advice. Tanks are expensive though as are plastic ones sadly, but they’re brilliant to use - I’ll personally not use a barred cage again since I like them that much lol. I’ll always recommend the ikea detolf as the best option since it is inexpensive but it is over 5 ft long. A lot of DIY info on it if you have a look around.
Zoozone 2 is available on jollyes for £50 in certain parts of the UK - much cheaper than anywhere else. Also does need meshing which isn’t too pretty but it’s a nice cage. Duna maxi multy looks good too but is a bit more expensive - no mesh required though!
Everything else is pricier, zooplus has a few nice ones including the eco habitat and marrakesh terrarium but very expensive (about the same price as a 4 foot tank really). I’d look out for second hand fish tanks or terrariums really, occasionally real bargains crop up