For the lower ball joints, I think when mine were done the parts were <$200, and it took <2 hrs. I did mine under supervision, and it needs tools and skills to prevent damage. If you need to ask, you might not be able to do it. They can be very difficult to remove.

If you're getting new wheels, do that first.

Then see how it behaves.

The Idler arm bushings are DIY if you have a good socket set, and have some experience. Try to score a set (2 vol, combined ~ 2" thick) of the manuals for your truck off ebay. They really help.

Don't do an alignment until AFTER all other changes/repairs/etc.

If the truck's never been off-roaded heavily, then it's very unlikely any of the steering stuff is damaged.

Get a grease gun, and start chasing down all the grease nipples on the front end, and the drive shafts, there are a lot of them! The truck is very user-servicable. You might want to get a 4x4 shop (or maybe a Mitsu dealer?) to re-pack the wheel bearings, and change the diff lube, especially if you've got the limited slip rear diff. You can change the diff fluids yourself, but an experienced shop will know what warning signs to look for. The front diff may not have seen much use, and hopefully no water got inside.

I'd be willing to come down from Vancouver to have a look, but the border crossing times are getting ridiculous. If you come north, let me know!