I have a Zamp 200w portable but checking the prices online recently and some stores have really gone up in price.
I did find this RV dealer in Wyoming with better prices
Here is a review
For a single battery you could get away with a Renogy 100w panel at $300 or less. I purchased mine this time last year and it was still $800 now its
You can purchase a separate panel, controller and cable and make your own.