Where can I find rainproof lab coats that are not disposible?

I am a dentist that is looking for rainproof lab coats that are not disposible. I want the washable kind. Look for safekeeping lab coats, for use in raining labs. For example,
ProMax
. http://www.ahsafety.com/product.asp?id=2.
For others:
. http://www.ahsafety.com/category.asp?cid.
I would just reuse a disposable lab coat merely wash it past its sell-by date first