Just wondering if anyone knows where I could get a replacement part for a Canon lens. Specifically my EF 75-300mm 1:4-5.6 III suffered a bad accident and the plastic ring that holds the front glass cracked. It still retains the glass just fine, it's just that dust has been getting between the two pieces of glass and it's impossible to get out. It looks like a pretty easy fix if I can only get a spare ring and maybe replacements for the tiny screws if I can't reuse them. If anyone knows a website or something that would be great! Thanks!