Check out the Taylorcraft.

A 100hp F-19 gets off the ground in about 350' and will climb at 1000' per
minute on a cool day. I've seen mine climb around 700 fpm at 70 degrees
with two of us on board. There are lots of them on floats. The 65 and 85
hp models perform very well too.

The factory is spinning up to make new birds: www.taylorcraft.com.

They will be available with engines from the O-235 to O-360.