Let me start by saying that I'm not an expert at judging the price of violins, but I am an expert in getting ripped off -- those are my qualifications.

Before you do something like that, I would urge to to check out ebay, etc. You can get Suzuki violins all day for $100-$200 bucks.  That ad is very short on facts and very long on hyperbole and claims which you can't easily verify.  Is it worth $500? Maybe -- but I'd be very skeptical.  There are too many reputable places to get violins that sound good and play well for $500 or less to take a chance on people selling stuff on ebay or craigsliist.  Those places can be OK for people with a lot of knowledge about whatever it is their buying -- but there are no great deals on anything on either of those sites.  Everything gets sold for at least what it's worth and sometimes a lot more. 

Lastly, I suspect the reason that the wood has been aged over 20 years is that the violin is over 20 years old.  If you look on ebay you'll notice that most of them were produced in the 1970's.  As far as it not being a a typical student violin, that's a stretch -- since that's all Suzuki made (student violins)  and they were sold by violin teachers that used the Suzuki method -- not that, that's a bad thing -- but it IS a typical student violin with a pretty hefty price tag for what it is. If I were going to make a offer on it, I don't think I'd go above $200 and I'd want to have it looked at by a professional before I paid that much.

There many reputable places (including Fiddlerman right here) that will be happy to sell you a  good violin at very reasonable price and will stand behind what they sell -- often with a money-back guarantee if you aren't satisfied.  For example, I just bought a Fiddlerman Concert violin here last week -- I'm not a fiddle player -- yet, but it looks and sounds like it's worth at least what I paid for it. it's easy to play has good tone, flamed maple back, comes with excellent strings on it, has a really nice case, rosin, a top notch carbon fiber bow, comes completely set up and ready to rock Bach -- plus it's only 400 bucks and there isn't even any shipping charge.  

Another avenue, if you don't want to buy stuff online, is to go to some of the local music stores in your area; parents sell their kids violins back to the stores all the time and that can be a really good way to find a decent student violin (albeit slightly dinged) at a good price -- if you go to a reputable store. That works best at the end of the school year though.

Good luck in your search.  I got one last week and dude -- it's fun.