Yes it does. Its aluminum and easy to flatten the end with a hammer.
No, 2 options; you can drill a hole completely through the shovel once you get the shovel as far up on the handle as possible and use a bolt. I recommend a nylock nut and cutting the end if it protrudes too far. Or you can use two 1/2" to 3/4" screws to attach. If you do it this way, drill SMALL pilot holes before trying to screw into the handle. It should be fine for a very long time. Before inserting the handle, inspect for warping and rotate the handle accordingly.
Label says 1.5" dia. The diameter at the seat is 1-3/8".