One year post-surgery, I'm finally able to ride again (somewhat!), and am jumping in by searching for a cross bike. A 49-51 cm top tube would be ideal (I'm short). Is anybody looking to upgrade and sell their old bike, or know a junior who just outgrew something this size? I'd like to spend under $600. Wheels aren't necessary if you don't want to part with them. Portland area a plus.

Thanks!