It looks like someone at the public library in Edinburgh should be able to help you out.
"Every public library service in Scotland now has a 3D printer available for public use."
Which is absolutely fantastic. If you head in there and ask I'm sure you'll find someone willing to help you out! The 3D printing community is pretty great.
I printed min in ABS since it holds up a little better to the shock than PLA - but it somewhat depends on what printers they have there and what materials they have on hand. A nylon copolymer would probably work ok as well. Ask them to print a couple for you and if another one breaks you'll have a spare.