Very nice to hear that you are interested in creating and ordering a Travel Poster from one of your trips. At the moment we are only shipping the posters to a small list of countries, you can see this article for that list: What countries do you deliver Travel Posters to, and how long does shipping take?
The reason for only allowing ordering from five countries is because it is a new product and we keep making new changes and are constantly gathering feedback to make the best version prior to opening up shipping to other countries! Hopefully we will be offering this option to all of our users, so keep your eye on this space.