I am starting the Camino Frances at Easter and I had naively assumed I could pick up a credential and a concha from the Pilgrim's Office at St Jean Pied de Port. Having read some of the other threads I am beginning to panic that I should have ordered one from my home country (UK). I do have a shell I could drill some holes in but what is the usual practice? If I have to buy them/ donate what roughly is the cost?