Your current version is as high as you can go with Photoshop CS6. You will have to use the DNG converter to create digital negative copies that you can open with what you have. There will be no further updates of Camera Raw that are compatible with Photoshop CS6. Here is a link to the latest version of the DNG converter:
Adobe - Adobe Camera Raw and DNG Converter : For Macintosh : Adobe DNG Converter 9.10.1
And here is a brief tutorial illustrating how to use it:
Camera Raw: How to use Adobe DNG Converter - YouTube
Take note that the DNG converter works on folders of images. Choose a folder when browsing in the DNG converter, but don't open it. If you do, it will notify you that there are no images to convert.