Cant take a die to the threads and fix them??..
You could drill a hole in the shaft and tap it,and use a 1/4" bolt and a fender washer to secure the wheel on,its not under a huge stress load really..(heck,in race cars they just clip on!)..
I have done just that to lawnmower crankshafts that sheared off when an impact gun was used to remove the flywheel nut,instead of coming off,it snapped the crank off,leaving the nut intact!..

..my shop class teacher showed us how to drill the center of the crank peice that busted off and the crank and tap the hole,and use a bolt to hold the flywheel on..
I always thout it was a risky "fix" but it does work!..if a bolt will hols a flywheel on spinning at 3600 rpm I dont think a steering wheel would be a problem..
If you would rather not do a jerry rig repair ,its not that hard to replace the colum with a salvage yard one..I've done a few,taks maybe an hour...hardest part is locating one just like yours ,same year,etc,otherwise things might not be "plug and play"...