live pricing of silver, gold according to kitco.com and live exchange rates

My company's website is on a wordpress site and we are selling bullion products. We would like to have in place a system where the products are priced according to prices at [login to view URL] + our own additional price. So for example, we are selling 1 ounce of silver. The price of 1 ounce of silver listed at [login to view URL] is $30. Our own additional price is $[login to view URL] the product I am selling on showing 1 ounce of silver is $32. If the price in [login to view URL] changes to $30.50, the product have to reflect $32.50 accordingly. We have many products and this should be applied to every one of them. We would require three exchange rates and this is in USD, EUR, SGD. Prices stated are in SGD. If a customer changes his preference to USD, and the live exchange rate is 1.2, our product which is SGD 1 - will reflect USD 1.2. This, too, has to be live. This should not affect the checkout process. The prices at checkout remains in the customer's preference. However, when he goes to the payment gateway, the information sent must be in SGD. We need this done in a day. If you cannot do so in a day, please do not bid. We will pay promptly once work is done. Thank you.