There is a sport shop in Canada called Wholsale Sports.www.wholesalesports.com they sell the Baush and Lombe Elite
15X45X60 for under 500.00 Canadian. I have never used one but according to articalls I've read it is not a bad spotting scope.
I'm pretty sure it is still more than the $300.00 you have allowed for a budget.(I'm asuming you live in the States) but it is probably your best bet.
Unless you can come across a good second hand one at a good price but I don"t recomend it.Its too risky.