Zen Cart Database Integration

I am starting a new collegiate sports merchandise site, which will be based on a pre-existing brick-and-mortar operation. The brick-and-mortar store uses Microsoft's RMS 1.3 (not the Headquarters version) point-of-sale system. Ideally, the website would tap into the same inventory data of the pre-existing RMS database. Otherwise, if this is too cost prohibitive, I need someone to transfer the item information from the pre-existing RMS database to that of the Zen cart database. With that solution, inventory control would be done manually, which is not preferable for my purposes but doable. Ideally, I would like the website database to work as a separate "lane" with the RMS version I currently possess. I honestly have no idea what the price range ought to be for this project, so feel free to add more detail via PM. If you can do the integration or transfer for less, all the better.