There is a good chance that with non-commercial non-luxury items, you will simply be waived through. The people who get nailed are those who file false declarations and wait for a random inspection. In order to prepare for payment, best to have the receipts with a table showing the current dollar value at a reasonable exchange rate (shaving a few bucks off the conversion to save <$1 is not worth the effort).
What is the alternative you seek? Best to provide the exact details of what you currently have booked.