I know I could make my own, but is there any good source? I am in the Northwest, but would be willing to drive a reasonable distance.
Just about any grocery store with a kosher section has it. I know I've seen it at the stores around Jenkintown, like the Acme.
Look in the freezer section in the supermarket, where they have frozen Empire chicken breasts. That's where I used to find it when I made the best matzoh ball soup - but it's been a while.
Just in case you need to make your own. A easy micro method.
SCHMALTZ - Rendered Chicken Fat (Pass)
8 oz. unrendered chicken fat & skin
1/2 med. onion, coarsely chopped
Place fat and skin along with chopped onion in a clear quart microwave container (such as a Pyrex measuring "cup"). Place in microwave oven and cover loosely (with a glass cover, plate or wax paper). Cook on high until fat is liquid and skin pieces (grebenes) are brown and crisp, around 6-8 minutes. Saves grebenes, after draining, for use in kugels, stuffing, etc. Strain the liquid fat and discard the onion pieces. Pour fat into jar, cover and refrigerate or save in freezer