Looks to be an 1988 Chorus model. The weight is a couple of pounds optimistic. The Peugeot literature spec'd it at 20.9 lbs. It was spec'd with 753, but not sure if that includes the stays, though the forks are spec'd as 753. One point to be aware of, assuming that I'm correct on the year, is that an original wheelset will be tubulars (this scares some people). Don't have the original price but 1988 SL/Chorus models were going for $1600+ US, so $450 sounds like a fair deal provided it's in good cosmetic and mechanical condition.