Yes, you can. MP3Rage is great for MP3s but also works well to change the file type of other kinds of file. I have successfully used it on a half dozen .sit files (Stuffit archives) already.

You can do this with any number of Mac file editing programs; I just recommend MP3Rage because I hope that more people will edit the tags on their music files, and this makes it easy to add in, say, the artist and album title for a given album.