You can try cleaning the hole and the handle taper really well to remove any oils or grease, and then use Loctite sleeve and bearing mount or 271 thread locker, or similar. The fit needs to be within a couple thousandths for the anaerobic sealers to set up. After they set it will require several hundred degree F. temperature to get it apart again.
You could drill the back of the spinner and tap a small hole and drill the bolt clearance thru the wheel then mount it and loctite the thread in leaving enough clearance to spin. I doubt it was ever ment to spin but through use its enlarged the mounting hole.
drill a hole for diameter of small Ball bearing at the end of the spindle 3/4 the way through. Use a boring bar to cut a relief inside the handle bore. Place pen spring in spindle hole and press ball into it. Slide handle on spindle so ball engages relief groove. Crank away.
You can also cut a slot into the spindle and use a expanding c clip.
Does the TH-54 have Zamak parts as do other many of the other Atlas machines? If so, rule out brazing as a possible approach. Zamak 5 melts at about 725 degrees, brazing typically happens at around 840 degrees. The part would melt before the braze.