Hi cherrycoop. If you Google Quail Hatching Eggs you'll find quite a lot of suppliers by post. As I've just this weekend ordered my own first batch, I can't give personal recommendation yet, but Oldland Quails looks good, I've bought equipment from them, and they do have hatching eggs but you need to ring them rather than ordering via website. see http://www.oldland-quails.com/ or email from their Contact button.
The person I've just ordered from also has a nice website which attracted me see http://willowtreequail.co.uk/default.aspx which is worth a look even if you order elsewhere as it has some good advice on incubation and care.
I don't think cold should affect eggs in the post as long as they aren't frozen, because they have to be kept cool before incubation anyway.
I shall be very interested to hear how you get on, so we can compare notes as we incubate our babies!
EDIT; Sorry i meant to say eBay, not Google, to get list of suppliers.