sounds very expensive, half that price is also a bit high
70-100 US dollars is more reasonable
It depends where you are. In the US, you won't find a Blizzard '030 for that price. Or at least not one that actually works and isn't a scam.
$250 sounds a bit high even for here, though. Half that, $125, is fair to slightly cheap, from what I've seen. Another option in the US, the more common GVP model is also good, if it comes with enough memory on the GVP simms. (If not, the GVP simms are a real bank breaker!)
There are also other cheaper '030 cards, but they have various other glitches and inconsistancies. (Apollo, CSA, and 50mhz DKB version, I'm looking at you.) Do some research, and see what you can live with.