This sounds like a gun that should be appraised hands-on by someone who knows Parkers (not me). As I read my (slightly out of date) value guide, a 28 ***** DH in NRA Excellent condition is just a little on the south side of ten grand plus 50% for the auto ejectors. You can add another 20% for a selective single trigger and 30% for a ventilated rib. An 80% DHE would be around $10,750 or up to $15,000 if it has the other options too.