Ooh I love this topic! Boat shopping is so fun. I'm afraid I'm no expert on canal boats, but we do have some members here that are. If you do not get a good response to your question, maybe post another thread titled 'canal boat', that will get some attention :-).
Welcome to the forum,
Aloha and welcome aboard!
Good to have you here on the forum. I don't know much about non-US boats so can't make much of a recommendation. There are a couple links after my signature and a book recommendation.
I do sail a club International Folkboat and find it to be a dream to sail but it is a little cramped in interior space with a narrow beam for a 26 footer.
Not sure what your budget is, but you may find Margaret Dye's book "Dinghy Cruising" a good introduction to canal (and estuary) sailing. And it will help make a Folkboat feel like a mansion.