the price is relative. if you really want it, and are willing to spend $350, then do so. i paid $350 for my grande, and it was not in near-mint condition (it had a few rough spots here and there and missing the carb airbox, a broken center stand, a few other minor things). but i really wanted a grande and was willing to spend that much.
my bianchi was near mint, but slow slow slow ... and i paid $330 for it. i've also gotten lucky and paid $50 for a carabela that was very nice and complete, but had a seized engine (still seized) and a "project bike" garelli (almost complete) for about $60 that never got around to running (it was stripped for parts to get another garelli running).
my personal opinion is that $300-450 is a fair price for a solid running moped that's in good condition and that you want. you can get lucky at find mopeds in the trash or get super good deals. you can also find mint mint condition "prize bikes" that will sell for lots and lots of money.
it's up to you. if i were you, casey ... i'd buy it. but i'm not you ... so i won't. it's not italian after all! ;-)