I have a 10' WaterTender. It is pretty stable, and can hold more weight than a regular Jon Boat. It's rated for a 5 hp outboard too. IIRC the boat only weighs 100 pounds.

http://www.westmarine.com/buy/west-marine--watertender-9-4-rowing-dinghy--11985504

www.hoosierpondpros.com

[Linked Image from lh6.ggpht.com]
http://www.pondboss.com/subscribe.asp?c=4
3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).