I could send you good knife for cheaper than retail, but not for $1 cheap.
Depends what kinda knife you want, for what purposes.
Just for fighting/defense, a stabber? Fixed blade, or folding?
I got some of these awesome
CRKT M21-14 folding knives. Have yet to see anything better out there.
The thing opens like a switchblade, is super sharp and rounded to a point, has flat and serrated blades, opens large (intimidating) but folds to halfsize, has a safety lock (no danger of folding on your holding hand in combat), is relatively lightweight.
AMAZING knife.
Think it sells for $60 (but on these sites it's $90!), would mail it for $35. Yours would be brand new.
Whatever knife you do end up with, I think you gotta practice drawing it, right? Maybe even practice putting it into something somewhat solid, so you don't hesitate or have trouble doing it when necessary in an emergency.