Look at a Water Tender.

It is short and wide and light weight. You need the width to make it more stable in the water. I have one and it's seen up to a 10 hp Merc outboard. I have had over 600# (plus me at 200+ pounds) in the boat too, and there was still plenty of freeboard.

https://www.westmarine.com/west-marine-watertender-9.4-dinghy-11985504.html

I believe you can also order them through Wal-Mart.

www.hoosierpondpros.com

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3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).