The tire size calculators I've seen show a 185/85x16 as the closest match diameter wise to a 600x16 but good luck finding a set in the US. Running a 215 will most likely throw your speedo off a bit. Just be aware that you'll be moving just a bit faster then your speedo indicates.

Save a life, adopt a senior shelter pet.
The three main causes of blindness: Cataracts, Politics, Religion.
Name your dog Naked so you can walk Naked in the park.