Magento Pre-order system

PRE-ORDER STOCK SYSTEM I purchase products in advance of my stock becoming physical in the actual warehouse. I do this in order to pre-sell the goods prior to receiving them in stock. I require an extension that can split customer orders on the front end, creating a physical stock order for immediate dispatch and also a pre-order (backorder). The client must be notified of this with the expected delivery date/s of the pre-ordered items (also, splitting the order more than once if there are differing stock delivery dates and notifying the client of this). In the admin section of magento it is necessary to view the physical stock level and the pre-order stock level/s, (and of course the pre-order stock level minus the customer pre-orders if the physical stock is zero). I use other companies that currently have this facility on their websites, therefore, I can show examples of these sites. i need somebody that has previously worked in designing a pre-order system in magento as I feel that the work will be difficult to explain to an amateur. I look forward to your bids.