I would say that although, you're account is technically worth $300, I highly doubt it will sell for that as know one will be willing to spalsh out that much.
The higher the value of the account that is to be sold the biggest lose of dollars there will be as prices can be over the top, from what people are willing to pay.
The price you should sell it for, I couldn't tell you but it should go for a fair bit.
Hope this helps.