No commerce_price field in product after Kickstart
The commerce_price field should be on products referenced by the display. Typically what happens is an importer will migrate all product entities first (which corresponds to each SKU in the remote system) and then set the product reference field value of a product display to point to those product entities. The SKU is unique, so it can be used as unique ID to reference displays to SKUs when you don't actually know product IDs.