VALUE OF HECKLER & KOCH MODEL 770?

IM TRYING TO FIND OUT HOW MUCH A HECKLER AND KOCH MODEL 770 IN 308 CALIBER IS WORTH.I HAVE ONE I THINK I MIGHT PART WITH...THE ONLY PROBLEM WITH THIS GUN IS THAT IT HAS A LITTLE PITTING WHERE THE MUZZLE BRAKE AND THE BARREL MEET(IT IS ONLY ON THE BARREL SIDE)ABOUT A 1/4 INCH IN SIZE.OTHER THAN THAT IT IS IN EXCELLENT SHAPE.

THANKYOU
EDDIE MARTIN