Well, current prices, you're looking at $40 kydex + $60 ESEE accessories, so $100 total unless you can find used stuff...
Alternatives:
Spec-Ops sheath, combat master or basic+pouch, short - will run you $50+, and you'll probably want to mold the plastic insert to better fit your knife (or order a custom insert for it, again Azwelke and others can supply)
Survival Sheath Systems also has a Spec-Ops "survival sheath" and a variety of other options you may find appealing.
Blackhawk sheath (similar to above)
Remington sheath (similar to above)
Scrapyard Knives canvas sheath (no frills cheap, it's too large and the insert is crappy, but the insert can be molded for a better fit - my RMD now rides pouch-style in one of these)