Replying to Intuition Liner vs Lightly Used Boot

So I've got a pair of boots that are pretty good, but not perfect. The liner is pretty terrible and I've been looking at picking up a pair of Intuition liners to see if that helps at all. I don't have a ton of money to work with right now.

After doing some looking around (kijiji), I've found a couple of options.

a) New Intuition Alpine liner
b) Lightly used Full Tilt First Chair's

Both are about the same price. Do I get the just the liner or do I get the boots and if they don't fit well, try the liners (I believe they are Intuition's?) in my current boots?

inb4 go to a bootfitter
inb4 Full Tilt's