The hand crank accessory should have come with a spare bolt. Usually when the HC does come loose I keep a screw driver handy eventually the machine and I come to an agreement if not I have an L shaped screwdriver handle so I can get some torque. My opinion is to use the original if possible.
I also replace the tubing on the finger that goes in the spokes. I have used tubing or I have sewn a bit of leather on the end of it. The black rubber one never lasts very long.