I came across this- http://www.raphnet-tech.com/products/gc_to_n64_adapter/ http://www.digitpress.com/forum/showthread.php?157110-GameCube-to-N64-controller-adapter-review The price might be a little outlandish, but it's a great fix for those of us who hate the crappy plastic joysticks.
Good luck in finding a Hori pad that doesn't cost you a body part. I never saw one go for less than $100 on fleaBay...
Going rate on ebay today seems to start around $60. Bought mine for perhaps $40 some years ago but it had a yellowed stick. Best buy ever for the N64. Wavebird support rocks thought.