I have a NP203 transfer case (Ford) for sale. Seems to be in good condition. Would make good candidate for 203/205 doubler. Remember, it is a divorced case, so you will need to drill the mounting holes - shouldn't be an issue though...
$125 - located in Park Hills MO. May meet in St. Louis, or between St. Louis and Park Hills on Hiway 55 or 67.