The axle ID is under the key for the left hub.
It doesn’t sound all that bent, probably can be fixed well enough… a descent back up axle can be a day saver. Indicate where you are located, and maybe someone will point you to a great kart shop near you who can sell you a new one, straighten your old one and be there to shave your hide another day. If they attend the same races as you, all the better.