Interesting idea.  If that doesn't workout, you could try to make the crank arm out of wood with a hole small enough to press fit and add a set screw.  You could reuse the handle from that crank.   
I can't see how a failure can occur.  It's almost a press fit to the shaft and the set screw pulls it even tighter.  It was touch and go sanding it down on the belt sander tho  -  fingernails got really close several times  lol