One of these


and one of these


and life will be good. Just measure your chain against the old chain or you can measure the chain in the big ring/big sprocket combination plus a few links. It's easier to make it shorter than longer, so if you're not sure where to break, go long and give it a trial fitting. Even if you accidentally get it too short, keep the extra links and you can add one with a second quick link. It will be evidence of your mistake until your next chain but will work just fine. Ignore anyone who says you can't use two quick links to lengthen a chain. I've never had one fail so why would a second one in the same chain make any difference?