Andy,
I used Edston and was pleased with the results. The gave me a nice quantity discount since I was ordering 3 for CVX-17s. Shipping was a killer, but since I was getting 3, I was able to split the shipping costs with others.
The windshields were an exact fit, and exact tint. They also got the compound curve right.
I found them on the old Glastron resources list
http://www.edstonplastic.com/