You can just purchase a download version. You will receive a serial number to use with this, and be taken to a page where you can dowload. But you don't need to use this download link, if you have already downloaded the software. You can just enter the serial number that you have been supplied with, into the software you are already using, and that will make it become licensed.
in other words there is no practical difference between what you get from the "download a trial" link on the Adobe website, and what you get from the "download purchased software" link.
