[nighthawk]

I have an 8HP outboard on my boat and the gas tank is a 3 gal nissan vented metal tank. The PO had it in the bottom of the port locker, but since it was open to the rest of the boat below, it stank the place up to high heaven. It currently resides at the aft end of the cockpit, which hampers raising and lowering the swing keel. I need to build an actual locker with forced ventilation and then it's going back underneath. As soon as I figure out how the PO got the hose to go through the thru-hull grommet with the quick disconnect end on it--Think I'll be visiting a hose fabrication shop in the near future.

 

[nighthawk]

Don't know what your transom arrangement is but the "Dingy Mate" might work, or perhaps it could sit on the cockpit floor?

Scepter Marine - OEM and Topside Fuel Tanks

Unfortunately, their wesite says they don't sell them in US

 

[nighthawk]

I can get you within .5 gallons of what you are looking for:

Vintage Hiawatha 2 5 Gal Outboard Marine Gas Fuel Tank Force Chrysler Sea King | eBay

Most everything else I see bottoms out at 3 gallons nowadays.