According to the 2010 Standard Catalog of Firearms the SBEII was introduced in the 2005 model year. So being a 2002 SBE II is doubtful. If you can lay your eyes on the weapon, then look on the receiver just below where the bolt locks in the open position. My receiver plainly says Super Black Eagle II there.
Either he has the year wrong or has the model wrong.
Also the Excellent condition price of the SBE according to above is $950. This means that the weapon is in "100% original factory condition without refinishing, repair, alterations or additions of any kind. It must be 98% with respect to blue wear, stock or grip finish and bore."
The Very Good condition price of the SBE is $650. This means that the weapon is in working order and retains approximately 92 percent original metal and wood finish. It must be 100% factory original, but may have some small repairs, alterations, or non-factory additions. NO refinishing is permitted in this category.
As far as the price goes it is smack dab between excellent and very good pricing for an SBE. I would carefully inspect, and fire the weapon to ensure it conforms with the above criteria. I'm suspicious that you are dealing with someone who has their finger on the pulse of the market just by looking at the asking price.
If it is an SBE II then Excellent price is $1000, Very Good is $650
One of the biggest problems, with buying used, non-collectible, weapons (particularly autoloading) is knowing how many rounds have been through the weapon and why is the person "really" wanting to sell the weapon.
Luckily the SBE is basically recoil operated. So I think that you are better shape than buying a gas operated autoloading shotgun. I have my Grandfathers Browning Auto 5 and my dad's Remington Model 11 that shoot well to this day.
My personal experience with used gas operated shotguns has been disappointing. I purchased a "lightly" used Remington Model 58 in the early 70's. This gun operated properly for about 2 hunting seasons and was back and forth to the gunsmith for a year with a quote "jamming" problem that was never fully repaired.
So the year after that I purchased a " lightly used" Remington Model 1100 that made it for 5 years and developed exactly the same problem with the same out come. I subsequently began purchasing pump shotguns and the SBEII is the first autoloader I have purchased since the 1970's as it is not gas operated.