Looking for a Good Short Dagger (about 4" blade)

[jstrange]

Gryphon M10 might work for you.

 

[Sirryacus]

How about a duct knife.

 

[Lycosa]

Take a look at the CRKT Yakanto.

 

[BOBO]

Shadow Tech knives make a good, affordable dagger.

 

[wensynch]

Here you go:

Tops Ranger Short Stop. USA.

That's the short version of the Ranger.