NMAC; OPPOSITE DIRECTION TFC.

Narrative

WHILE ON THE SID (PRDO2.PDZ) OUT OF ONT; WE WERE CLRED TO 7000 FT. WHILE CLBING THROUGH 5500 FT; ONT DEP CTL CALLED OUT TFC AT 12 O'CLOCK; 5 MI; ALT UNKNOWN. TCASII SHOWED THE TFC BUT WITHOUT ALT INFO. WE IMMEDIATELY ATTEMPTED TO MAKE VISUAL CONTACT. WHILE PASSING THROUGH 6000 FT; WE SAW THE TFC RIGHT ON OUR NOSE ABOUT 1 MI AWAY. FO IMMEDIATELY LEVELED OFF THE ACFT AT 6300 FT AND THE SINGLE ENG HIGH WING ACFT PASSED ABOVE US AT 6500 FT (ESTIMATED). HAD WE NOT SIGHTED THE TFC AND LEVELED OFF WHEN WE DID; A HEAD-ON COLLISION WAS LIKELY. THERE IS NO INFO ON THE LIGHT ACFT. HE SEEMED TO BE ON HIS CORRECT VFR ALT NAVING ON V186 INBOUND TO PDZ. I DON'T THINK HE EVEN SAW US COMING UP AT HIM AS HE MADE NO EVASIVE MANEUVERS. OUR LEVELOFF WAS FIRM BUT SMOOTH; AND NO ONE IN THE CABIN WAS AWARE OF THE INCIDENT AND THERE WERE NO COMPLAINTS OR INJURIES. WHAT COULD HAVE AVOIDED THIS SIT? IF THE CTLR HAD GIVEN US OR WE HAD REQUESTED A TURN OFF COURSE AND AWAY FROM THE TFC WHEN IT WAS FIRST ISSUED; WE MAY HAVE BEEN ABLE TO PASS TO ONE SIDE OF THE TFC EVEN IF WE HAD NOT SEEN HIM VISUALLY. HOWEVER; OUR FIRST REACTION WAS TO 'LOOK' FOR THE TFC. THE CTLR SAID NOTHING ELSE UNTIL THE TFC WAS BEHIND US. BY THE TIME WE ACTUALLY 'SAW' THE TFC; WE HAD VERY LITTLE TIME AND AIRSPACE TO 'AVOID' HIM. FINALLY; IF THE VFR TFC HAD BEEN REQUIRED TO HAVE MODE C ALT CAPABILITY; ESPECIALLY ON A VERY BUSY DEP CORRIDOR; THE NEAR MISS WOULD NOT HAVE OCCURRED. EITHER THE CTLR OR TCASII WOULD HAVE WARNED US IN PLENTY OF TIME.