User blog comment:RetroKitty/Perry the Platypus T-shirt?/@comment-88085-20120421195528

If you still fit into youth sizes, you could try this shirt. Otherwise, you can try this one in adult sizes. Unfortunately it looks like the adult size small is out of stock, so if the youth large is too small, then you'd have to go up to a medium or wait until they're back in.

I also sell Phineas and Ferb fan t-shirts in my spreadshirt shop. Shipping to the UK is a little bit pricey, but if you get a couple friends together and split the shipping, it wouldn't be so bad. You can change the shirt color on most shirts if you'd like. Also, if you see any shirt that you'd like to buy that's only in men's, I can make it available in women's or kids' sizes. Just let me know.