I bought a '74 W200 Power Wagon a couple months back.
One source for you might be VintagePowerWagons (see link at bottom of this post) which has parts up to 1971.
It doesn't work well for me as I have a '72 - '80 style, but it should be a good source for you.
For my '74 truck, DodgeTruckParts.com works well.
I will check my Bookmarks and see what others I have.
JC Whitney (though generic) is another potential source which oftentimes has parts you need.
Also, some parts are common between cars and pickups. I noticed the sun visors on my pickup appear to be the same as the ones on my '71 Charger. The outer door handles on my truck are the same as A-Body Duster/Demon door handles.
http://www.vintagepowerwagons.comDC
