Regardless where you buy, the entire window is the only way to purchase, even from a salvage yard.
Have your Winnebago serial # handy when they ask for it.
__________________ 2000 Winnebago Ultimate Freedom USQ40JD, ISC 8.3 Cummins 350, Spartan MM Chassis. USA 1SG, retired;PPA,Good Sam Life member,FMCA. "We the people are the rightful masters of both the Congress and the Courts - not to overthrow the Constitution but to overthrow men who pervert the Constitution." Abraham Lincoln
Hence dealing with the factory. The lower piece is just a c-channel along the top it rests in and then the dial bar gets glued to it. Its a 5 min install. No need for the whole window.