If it was originally a 383 car then it won't be a real N96 car. I just bought a real shaker hood N96 4-speed 340 Cuda last week that's been a drag car for the last 30 years. I'll race it for a while before restoring it. The N96 option on e-bodies was only available with 340, 440-6 and 426 hemi. B-bodies also use the N96 option code but it's for an air grabber hood.
As for value, it's always hard to tell. Even the clones are bringing good money nowadays. That car would have brought around 30 to 35 here in the U.S. with the current economy. If it was a real shaker hood car then it would have brought 50-55.