If its in good mechanical shape, I'd say it was a reasonable deal. 95% and higher they're averaging over $400 in my, albeit short, track, too few prices for a trend:
Smith & Wesson Model 38 Revolver in .38 Special. 2-in Bbl. Bluebook of Gun Values (30th Edition) indicates between $350 in 98% condition and $450 in 100% condition for this gun. I have 9 recorded prices for this model gun from $300 to $625 over a period of 0 Yrs 4 Mos ending November 3, 2009. The average price as of that date was $430. No refurbs, no refinishes, regular sights, all represented as 95% or better no special editions, no distinctions for box, papers, tools. Current or last MSRP is $462.
The Model 36s are about the same. I just bought a Model 38 that was perhaps a little more worn than what you're describing. Paid $240.