Hello Wendy and welcome to the forum. I must say how lucky you are that you never shop. I hate have to go shopping.
I'm not sure where you would find flake salt, but I know that I can source it at the local supermarket here. Also I can get bulk bags of salt from the stock feed company, and then again I can also source some from the local wholesale butcher. Sadly rennent is something that I have to get from a speciality shop down south. I can't buy that locally, so you are lucky that you can.
So I would think any three of those would be worth following up.