I would post Jessy's picture and ask if anyone's got just one or two full-grown hens they could spare for her so she doesn't spend all winter alone. I only guess that she's an olive egger.
I wish you the best of luck!
I absolutely would not put anything with her that's smaller than she is or she'd peck it. If you bought chicks now, it would take minimally 3 months, more like 4 months, and 5 months if it's a silky, before you can blend them all together.
With adults, you pay more but don't have to deal with...