The problem described isn't a technology problem. It's a business domain problem, and it should be solved by fixing the domain modeling. The example doesn't uncover any problems with REST architecture.
If prices are changing and you need to capture them, the "Product" concept isn't enough. You need to model the concept of price, and perhaps price change events too. So a customer doesn't buy a product, but a product together with a "ProductPrice".
If prices are changing and you need to capture them, the "Product" concept isn't enough. You need to model the concept of price, and perhaps price change events too. So a customer doesn't buy a product, but a product together with a "ProductPrice".