Before installing any pkg, you must first:
Code:
sudo apt update
In your case, after updating, post back results of:
Code:
apt policy cups
You mentioned that you monkeyed around with your system something awful. Try to recount the things you did. Post them point by point. Did you do anything to your sources.list? Please post results of:
Code:
cat /etc/apt/sources.list
Last but not least, please post your output between [CODE] and [/CODE] tags for clarity. Or highlight the output and use the button in the *Adv Reply* toolbar.