Keep the gray plastic. Remove black clip around the vertical wheel post in the gray plastic. Remove wheel and wheel post. Buy new wheel. Installl new wheel. It will be easier to find a new wheel once you have the old wheel out so you can take measurements. but it’s likely something pretty standard, off-the-shelf. Wheels are something that companies buy, they rarely build them themselves. They typically come as a castoring assembly with wheel, axle, spindle, and attachment post in a variety of common sizes and with a dizzying variety of actual wheels.
Yes, you could probably use a laser furnace if it was cost-effective at those power levels. But it’s not even close. Arcs are and very practical in almost every sense and ridiculously cheap besides the power they consume. And a laser would consume more.