Greenheart
Well-Known Member
Please, tell me there's a chap in a shed by a river in India, accepting orders for those via ebay? 
What you need for ultimate torque at low revs is a steam-engined outboard
Stern to Stern would make more sense.Tohatsu do a 6hp extra long shaft, 25 inch, with a larger dia low pitch prop. Sometimes called the Sail Pro. See http://www.onlineoutboards.com/Tohatsu-6-hp-MFS6CSPROUL.html
However on a head to head tug of war with a Seagull Barge Pusher my money would be on the Seagull.