No idea what the prices are like in the US but that's what a used model is worth here.
And that seems awfully expensive for a mobo.
Have a look on craigslist and eBay for that model, if you don't find it, look for a similar viao laptop.
You'll get a rough idea of what it's worth.
If you're listing it on sites like Craigslist, over state the price a bit, people try to haggle all the time.