Autofill an attribute with a price value

[CFGJewelers]

My Magento store has item prices that flucuate with the gold and silver market values and I also have an eBay store. I am using the M2E Pro extension to synchronize the two. The problem is that the precious metal market can be volatile from minute to minute and I want to be able to be competitive in my prices. Is there a way that Magento can autofill an attribute that the M2E Pro uses to synchronize my prices between my Magento and eBay stores?

[ptomter]

This is not something that is default that Magento can do out of the box as far as I know.

Think something like this would be a solution.

Create a product attribute with value "Silver" and "Gold".

Use a webservice for Gold and Silver prices. ex. http://www.freewebservicesx.com/GoldSpotPrice.aspx

Then create a cron script that runs x times a day, and update Products with attribute value Silver/Gold, with new price.

In the cron script you create a rule how you define the new price.  If you have a base price defined on each product you use,  calcluate from weight etc.

Think this is the most simply and fastes way to perform this. Then you use the normal sync function from Magento to M2E Pro