UK owners, any recommendations for large orthopaedic beds please?

I have a 4 year old lab and a 3 year old golden, I know they’re young but they’re both prone to hip dysplasia + other joint issues which is why I’m looking specifically for orthopaedic beds

It doesn’t need to tick every box, but other features I’m looking for are: water/moisture resistant lining, machine washable cover, minimum of 4” thick, heat regulating (the golden is a fluffy boy who overheats easily)

Ideally the design would be a mattress or would only have 1 head rest (they like to sleep sprawled out)

I’ve seen the beds available on VetRelieve and Big Barker and whilst they look amazing the price is just a bit too high (Big Barker only ships from the US so it’s the shipping costs that push it over)

Thank you for any recommendations