My Ringcraft club isn't very expensive a small anual membership fee and then a couple of £ a week.
In all honesty you really need to seek the opinion of someone who is successful showing the breed in your area, they should also be able to point you in the direction of a ringcraft club.
Wether Grandparents were successful doesn't always mean that progeny will be. There are so many things that can go wrong eg, incorrect bite or undescended testicles so lot's to think about.
I don't thinka vet will be able to tell you if your puppy is show quality