Virtuemart product snapshot in Joomla 1.5

I am running a Joomla 1.5 site with Virtuemart. I also have two other sites with Virtuemart stores on the same server but different MySQL databases. The Virtuemart productsnapshots plugin allows me to include snapshots of virtuemart products into content. I wish to modify this plugin to allow me to display a snapshot of a product from one of the other databases, ie not the current Joomla site database. I am assuming I will need to provide the plugin with the database host, user and password details and am happy to have these hard-coded into the plugin code but would rather be able to set them as plugin parameters. I have attached the plugin I am currently using which provides snapshots of local products. Note that this has already been slightly modified for layout of the product snapshot.