Hi, Shadowjack -
Another path, which will work at least until you can find the correct plugin, is to get
GraphicConverter. GC can convert most any graphic file format from/to most any other, any platform, including RAW.
GC has lots of nice features - cataloging, slideshow, batch conversion and renaming, and more. The batch conversion allows converting a folder full of files and folders, many thousands of files at a time, in one operation. This can be handy for those times when a whole bunch of files need to be converted from one format to another.