I know nothing about that knife, nor much about Cold Steel knives in general. To me, that looks like a hidden tang? If so, you can drill the rivet out without too much trouble, but the handle stands a good chance of being molded to the tang. If so, this would require grinding, cutting, sawing, in general anything to demolish the existing handle. Once you've got it off, you can clean the tang up and make a new handle.
BEFORE you do all that work, you might wish to make a new handle from a chunk of cheap wood for a hidden tang, fit it up to a small tang. Once you feel like you've got the practice made with tang slot cleaned out, then and only then decide if it's really worth all the hassle.
Good luck, and be sure to keep us posted on the progress.
Ken H>