We did the same over here in Spain, purely down to unavailability and cost!! DH managed to get all sizes from 15.5" right down to 2.5" square templates out of less than a metre length, The cost was next to nothing in comparrison to the 40 euros that I had to pay for my 24" X 6" ruler :shock: :D I used a CD marker pen Loretta, but it does wear off and you have to redo it as necessary :D
Here's a link to the topic:
http://www.quiltingboard.com/posts/list/8109.page