A retail price, separate from the selling price
List price or MSRP on the product itself. Import, export, and the API keep it. Hide it if it is only internal.

The selling price is what the shopper pays. The retail price is the list / MSRP you keep next to it — on the same product.
You set it in the product editor. It is saved on the product. CSV import and export carry it. The API exposes it as product_pricing.
If the retail price is only an internal list price, you can hide it on the storefront. Shoppers then see the selling price only.
Open Products management, then the product. The field is retail / list price. No extra screen.
Questions about retail price
Products management → the product editor. The field is retail / list price.
Yes. CSV import and export carry it. The API exposes product_pricing.
Yes. Use that when it is only an internal list price.
Set a retail price on a product
Already in the product editor, under Products management.