Buck - Phrobis 4-line value and parts needed questions

[Loon]

Years back, I bought used what I thought was just another military knife copy.
I have 4 LINE M9. The blade is a silver matt finish and has only sheath scuffs and a perfect egde. Phrobis is stamped in the handle guard at the blade edge.

"M9 Phrobis3 USA Pat. Pend.", is on one side and the other side says, "BUCK 188 U.S.A.>" .
I have the Phrobis stamped plastic molded sheath with the stone intact under the rear webbing and the cutter on the bottom and a ITW Nexus latch.
I seem to be missing the front pouch and the upper belt piece.
Any idea what this is worth as it is and where I can locate the missing pouch and belt attachment part?

Thanks
Loon