Hi, we recently moved into a post-WWII cape cod (I think), built in 1946 Most of the house is original. In the kitchen there is an original Nutone vent fan above the stove. Check out the image included in this thread. I can't find a replacement filter for this vent probably because it's so old. Any ideas where I can get a vent filter for this Nutone vent fan? Dimensions are approx: 12" long x 8" wide. Thanks for your help.