Slim External Firewire/ILink CD-rom/dvd/cdrw/combi

I have just purchased a Sony Vaio srx41p and am looking at getting an optical drive. Does anyone apart from sony sell Slim portable drives that will work with the ilink port. Presumably the seperate power connector and the ilink port can be combined with a connector to give a 6 pin powered firewire port to connect a drive to. What drives would you recommend. I would get a sony drive however the £400 they charge for the combi is rather expensive imho.