First unicycle for 7 yr old

I am trying to help a friend locate a good used unicycle for a 7 year old beginner (Cincinnati, OH). Does anyone have information on what would be best for this age group, and do you know of any used beginner wheels for sale?

Thank you,

Scot

I started riding when i was 4, i believe i used a 16inch all the way until up to about 8 years old then i moved up to a 20inch miata. But my 16inch was my trials uni. Is he looking for more of a freestyle unicycle to just ride and do basic tricks on or go offroad, muni, trials, etc…

This will probably get them started for cheap. I’m pretty sure you’ll want a 16" so check on the size.
http://www.unicyclist.com/forums/showthread.php?t=85627

Ohio
http://video.google.com/videoplay?docid=-1442642404028856664#