What type of skills would you be practising or learning from scratch?
Do you do superpipe, freestyle?
I would definitely be looking for an el cheapo round one. Not perfect, but they can be found all day on CL for $100 or less and I wouldn't be looking to spend any more.
I would be looking to work primarily on different grabs and spins.
"People say that marijuana smoking is going to get in the way of my career. I say to them that on the contrary, my fighting career is getting in the way of my marijuana smoking." -Nick Diaz