Nokian makes a 215/55R16 XL tire in their WR line.  The diameter and load rating are both close to stock tires but they are a little wider.  Your 7" wide rims will accept the extra width.  Phil from Campbell River runs 16" rims and Nokian tires on his van but I am not sure of the exact size and model.  Check out www.nokiantyres.com for more information. (click on the North America button)  Kal Tire sell this brand in Western Canada.  I have this tire in 205/65R15 XL on our van and have been happy with them.
George,
'85 Westfalia