Not meaning to get up on the pew so to speak, but you need to start wrenching. You'll save money (from some to a LOT), you'll get to know your truck and you'll learn sumpin' along the way. The D50/MM is a relatively simple beast to work on and being a rear wheel drive you actually can get your hands down either side of the block to reach stuff. It's annoying that some Mitsubishi second gen engines suffered from crankwalk, so going back to a 1G will make it tough

I have found a few online articles about 2G crank failure and some have gone into depth about what is eating thrust bearings in them. This one is a good write up on theory and diagnosis -

https://magnusmotorsports.com/crankwalk-theory/