When needing to enter several past company product orders, we recommend entering orders that only contain the totals from the original order. You'll save yourself time and the frustration of trying to get the order totals to balance (due to price changes, and other variables) by adding the products from those orders into your inventory by Taking a Physical Inventory Count, and then Creating a Mock Order.
If your on-hand inventory amounts are mostly accurate and you only need to enter a couple of product orders, Edit Physical Count Directly On the Product List them then Create a Historical Inventory Order without Changing On Hand Amounts.