
Pup will be fine. Try and spend a bit of time at the breeders playing with him/her first so tiredness sets in before you travel. If you are going to crate in the car, put thick newspaper in part of the crate, so if an accident occurs it won't matter. Something warm and cosy in the other part so he can snuggle up, preferably smelling of mum. If you are viewing before picking up, take an old cardigan or similar to leave at the breeders so she can put it in with mum before you pick up puppy and pup should settle better with mums smell.
Tip: Take plenty of kitchen roll, Bounty is best for mopping up, be it car sickness or accidents.
Good luck, how exciting.