Easiest way to do this would be to create a tga with an alpha channel set to 100% black, and apply it to some random hilt. Since JA is weird it probably requires a shader for that too.
To get rid of the blade you simply edit the image files that are used for a specific colored blade (i think you make the image all black and no blades will show up in game).
Then you replace the sounds with empty wav files.
I made a chainsaw a while back and that's what i did.