This is a Randall "Gambler" Push Dagger Boot Knife.  I don't believe they make this knife or handle any more.  At least it is no longer in their catalog.

This knife is 8" overall with a 4" double edged blade that has thumb notches on the spine.  It is made out of 3/16" stock. It features A black Micarta Barber handle.  It comes with a brown heavy duty Randle clip on, slip in boot sheath.

If you can find one on ebay, you will find my price is lower.  These knives are hand made and Randall is currently taking orders with an expected delivery date of May 2030.