Son,
Nice to see you here.
Matt can fix you up just right, however of great importance to a dirt-dart or ground-pounder is a good sheath.
Kydex, or heavy duty nylon with a kydex stiffener is the most durable, leather is a distant second from most makers.
Busse, Becker, Strider, Mad Dog, all have some good nylon or kydex sheathware. So does some of the K-Bar high end models.
Eagle Industries makes a fine nylon sheath with kydex liner that will fit a K-BAR sized knife.
For leather, Randall knives (Sullivan's leather) and Kenny Rowe
make excellent sheaths.
The last thing you want is a blade poking you in the leg because of a bad sheath. If money was no object, I would probably go with a combat fighter from Walter Brend in D-2 or 3V. D-2 is more corrosion resistant (prob. not a factor in the Middle East), 3V is tougher and will hold an edge better.
RJ Martin also builds a fine heavy combat blade.
On a budget knives from Mad Dog, Busse, Trace Rinaldi, Matt Lamey, and even some production stuff like the Busse Basic 7, CS SRK, Recon tanto, Recon Scout, Camillus CQB will make fine companion blades.
If you like paracord wrapped sharp prybars, Strider knives are very tough.
You need a tool more than a weapon. Sheath security is more important than a quick draw. Low-maintenence (Quality Stainless Steel, semi-stainless (D-2, 3V) or coated carbon steel) is also something to keep in mind.
Personally, as you have already contacted him, I would have Matt Lamey make a knife similar to shape ofthe 7.5" Fisk Military with a light swedge on -one side-of the blade with a G-10 or micarta handle.You want about .020" thick edge of D-2 or 3V. Satin finished with a bead blasted handle/guard and a thong hole. I would then have Julie Marx checker the handle about 18 LPI (rounded diamonds). I would then have a good kydex setup made by Bob Bailey or On-Scene Tactical, Blade-Tech or Edgeworks. In the kydex sheath I would have a pouch for a good multitool and a flat medium diamond hone epoxied to the backside of the sheath.
Good Luck.