I've only seen a few of the Shaw Brothers stuff and bits here and there, and obviously Bruce Lee's stuff.
Loads are on YouTube which is great, nice and easy.
Spiritual Boxer (1975)
https://www.youtube.com/watch?v=b6TsiqmgYKE
Death Duel (1977)
https://www.youtube.com/watch?v=ImGWJcP6XgM
The Boxer's Omen (1983) is a lot of fun, horror/black magic kung fu type deal:
https://www.youtube.com/watch?v=R6agHON0X4s
#kungfu