I have had a look around the usual sites. Nothing of real quality really stands out along with a . There is some PAD stuff and something called a "Wilga" along with a raft of repaints for commercial products.
The Wilga is downloading right now and offer several model types.
I did look at the Virtualcol DHC3 Beaver which is very cheap and based on the screenshot looks OK. I have experience of other VC products and are quite easy to get to grips with.
Somewhere in the back of my hangar I have got the Carenado C185 (Bushwagon) which might be worth installing into FSX and then copying over to P3D to see how it performs.
...a amphibious trike...