I know the feeling, I remember that from my last prep. I know Palumbo always says you just need to up your sodium, but I only get cramps when I drop my potassium-containing foods.
There's something called "half-salt" or "low-salt". It's basically table salt with a higher ratio of added potassium for people with High blood pressure.
It's way cheaper than Potassium pills, and each teaspoon contains 1.360g of potassium/1g of sodium.
When keto dieting, i would recommend taking upto 5g sodium, and 3g potassium, although you can get away with half that.
For balanced diet cut, you have to experiment and find the right dose.
You can find this product or a similar product at your grocery store, or drug store.