wcondra

Iowa80.com was the cheapest for me when I needed a front hub cap a few years ago. 

I also have a 2003 Windsor PBDD. I replaced my Norcold with a GE model GWE19JSLGFSS. I made the decision to remove the furnace to accommodate it. However, after the furnace was removed, my shop said they could make it fit if I wanted to put the furnace back. Since I had never used the furnace, I said no, go ahead. It does protrude about two inches into the hallway, but that has not been an issue. Did the conversion two years ago. 
 

I found a replacement at iowa80.com. Just checked and the current price is $17.99

I bought one last year online from Iowa 80 truck stop. They have an excellent web site that walks you through the product determination process. Less than $20.