You can do it yourself. All you need is Photoshop or any other image editing software that can open .dds.
1. Download
this (It's for opening the .gfs packages)
2. If you're using Photoshop, download
this plugin and install it. It will allow you to open .dds files.
2. Go to Steam/steamapps/common/Skullgirls/data01, that's all the art assets. 'ui-artgallery' is the art in the art gallery.
3. Drag and drop the desired archive into the program in step one. It's not hard to use so figure it out.
4. Open the now extracted folder and drag/open the files you want to view in Photoshop. Save as .png if necessary or whatever.