You no doubt want to stick with a 700 wheel, but if you didn't you could put a trek threaded fork from a 800,820,830,850,930,950 MTB style bike and get the canti brake bosses, and lower eyelets, these take 26" wheels.

You could also get a threaded trek fork from a 700,720,730,750 multitrack with canti bosses.These take 700c wheels. They also have lower eyelets. I see these forks on ebay. Trek Cromo forks.