Are there any other sources where I can download ZC?

www.google.com, search for "zelda classic" in quotes. You should get a few different sites on the first page.

Try the links on zc again. They might be mirrors. It worked for me a few days ago.

Yeah, if a mirror doesn't work just hit back on your browser and try it again. You may have to do it a few times to finally get a mirror that works.

the ones hosted on gerudo.net are mirrored by me. if there are any links that are broken, please let me know.

if there are any official releases or other files i do not have uploaded, let me know where i can get it and it will be mirrored as well.