Quickbooks Plugin

We need a Quickbooks plugin created to import data from a MySql database. We have a custom application for our client that they use to take orders. We need a plugin for Quickbooks that will retrieve customer data and order info for each order and import it into Quickbooks so that they can generate invoices and manage all other accounting from within Quickbooks. There will probably need to be information imported into up to half a dozen custom fields that can be added to an invoice. This should be done with the Quickbooks sdk and should be a new menu item "Import from Website" accessed from within Quickbooks. User will click on the menu item and all records that have not been previously imported that are ready will be imported automatically and invoices generated for them. Probably marking records in source MySql db as imported would be the easiest to track what has already been imported, however, this is up to you. It will be used by more than one employee so you'll also need to ensure only one import is running at any given time. Again, this could be a flag in the MySql database or Quickbooks database. Whatever works.