Hi Marisa, if you're worried about shipping cost then maybe you should consider rescuing a glider in need off of craigslist? I'm sure that there are a couple in driving distance. That's what I did when my little one needed a friend. I have to say that even though I
really wanted to spend the extra cash and get either a WF or a mosaic joey, I'm so happy that I decided to save a glider from poor living conditions :) It's just another option and in the end you will be making two gliders extremely happy.
Totally understand about the parent thing! I was in the same boat. You just have to explain to your mother that they're social creatures and that your little boy needs a friend. You also might want to throw in there that having two is not much more work than having one. I know that my mom is still afraid of them, like she won't enter my room if I have them out at night, but she says that although she did not want me having more than one she understands and really can tell how much happier they both are.