> The crate i require is only needed for somewhere for him to sleep when we are there,so it needs to be able to fit in my car,unable to fold the seats down
If in doubt you can go to Pets at Home and they will let you try the crates in your car. They have display crates you can practice with, they also have fabric ones if you want to give one a go. Dogs are allowed in store so you can see what is the smallest your lab will fit in. You don't have to buy from them if you decide not to.
I have a wire haired vizsla - he uses a 42" crate at home but can happily fit in a 36" one for overnights.
Lots of different options
here - including detailed measurements
If you don't have much room after luggage you could try renting a crate. I found one company in Windermere that deliver - see
here. Alternatively put a wanted ad on here - some of us locals might be able to help out! :)