Hello Sunday Mornin ~ at www.MitsubishiPartsCentral.com (it's a Texas Mitsubishi Dealership Parts Dept web site) they've been great for me especially a now retired parts dept guy named Gary which I think he still helps them from home if no parts guys are around when needed... Anyway, in my experience with the ignition switch, Gary was able to get me the last one in stock for my 1986 truck... The tumbler lock is separate from the ignition switch but I never tried to buy one of those... I did need to replace my ignition key because I lost it in the ocean at Bellows beach (duh) Gary sent me factory Mitsubishi key blanks which are still available (abt $7.00 each..?) Please look at my photo album with photos of the ignition switch because it does not use all the connectors available but I (think) similar ign switches that use all the connections are still available & might be able to modify to use in our trucks..? Google images of ignition switches (or tumblers) for Chrysler products in years of vehicles near our year vehicles... If MPC can't get you a new tumbler lock then maybe a foreign source from Australia, Thailand or Singapore has em ~ use the google image search method & the truck is called a L200 overseas...

Enjoy the Fix,
George