I doubt you can find one that will withstand a lot of vinegar, but, any hardware store or one of the Big Box stores, will have one that will work in your sink. Take the old one with, so you get one similar.

I think it originally came as a set with the faucet. So, I was wondering if the connections under the sink that attach to the release handle on the faucet are proprietary or need to match a certain connection type or if they are all universal..

Should be a universal one, but, take old one with you, and you will be sure to get it exactly right.

What is the finish that was ruined by vinegar?

Some kind of material with a brushed nickel appearance.

it wasn’t even straight vinegar. It was mostly water with white vinegar added.

That's really strange. I use vinegar to clean those things!

Since it's already messed up, might as well try to fix it--unless it's plastic.

There are a few different types of drain stoppers so you'll have to look underneath and see how it's connected.