Yes you can replace it yourself. It drops into the upper ball joint hole, and then the ball joint fits in it. It's an eccentric so you can get some adjustment there...
They are about 50 bucks at Napa.
They are camber bushings or alignment bushings.
All you need to do is figure out what degree bushing you need, then install it with the correct clocking so that you get the caster and camber within specs.
Your also going to need to set your toe because the lift threw that out as well.