so you have a '85 westy..and your drivers side slider window is  broken?
the westy slider windows on the drivers side fit  '80-'91.. they are easy
to find.  i have several of them from parted  out aircooled vanagon westys.
 its the PASSENGER side '85-'91  westy slider that is hard to find.

why not replace yours with the correct westy slider window??  i dont
understand..

    anyway..  yes a 50-50 passenger van sliding window  will fit in there..
 but you cant use your westy screen. i have tons of  those windows.   i
think goWe$ty or busdepot may offer some kind of  aftermarket screen for
passenger van windows.. im not sure..  or like jim  A. said, you could just do
what ASI/Riviera and Country Homes Campers  did..and screw a metal framed
screen to the outside of the window......

In a message dated 7/15/2015 12:32:48 P.M. Eastern Daylight Time,
msouth@GMAIL.COM writes:

85 Westy  full camper.

I would like thoughts on replacing the driver's side 70/30  window (the
sliding part broke) with a 50/50.  Someone sold me a bus  window (y'all
helped me figure out what it was, actually) as a Vanagon  window, then
stopped returning emails.

I happen to have found  someone locally who could swap me straight
across--he needs the bus window,  and he has a 50/50 split vanagon window.

I understand that the stock  screen won't work on it.  Anyone have or know
of a fix for  that?

Someone in a previous thread suggested eurocampers.com, but the  only
vanagon screen I see there is the replacement for the stock  one:

http://www.eurocampers.com/search.asp?keyword=screen&sortby=0&page=3&catid=

Anyone  had luck making their own, for example?