Ok, I am looking for a new proportionsing valve for an 81 Jeep CJ5 ...it seems like they're all on back order, and even if they're in stock-they're like $400!!! Anyone know where i can get one, or know of a universal that will work for me?? Thanks BTW....right now, there is ONE brake working. Somehow somethin is fubar, what i dunno what. Bled all the lines and the rear driverside locks and the rest roll.