From what I've been able to find out the CD was made by Sabatti of Italy.
My 95 Std Cat. of Firearms lists the Diamond grade O/U, as EXC. $700, VG $625, Good $550, Poor $400, remember those prices are from 1995. And The NRA edition may add some value to the gun.
Gander Mtn. has a NRA Diamond edition listed for $899, but then many of the guns they sell are over priced.