Check with your local Mitsubishi dealer, I don't remember paying much more than the dollar amounts for my replacement mast that I got for my Montero. Factory part, was not much money, way cheaper than a new ant/motor assembly too.

'92 SR Montero, Green, with 31" Yokohama Geolandar A/T Plus Tires, Mitsu factory fog light kit, on-board air compressor,Sony Radio and 10 disc changer. 213K and counting.....
Stock & Happy otherwise