The new Tohatsu 4-strokes are pretty light weight in the 9.8 to 20 hp sizes. The 9.8 carberated model only weighs 81.5 pounds in a short shaft. The 9.9, 15, 20hp fuel injected models all only weigh in at 95 pounds in short shaft models. Weight doesn't have to be a problem.
There's paint and then there's paint. If it was me, I'd try an oil based porch floor paint. Keeping the boat in a garage should make a big difference too.
Elgin was just a brand name used by Sears. For instance the early Elgin outboards were made by West Bend. The boats were built by various manufacturers and rebranded Elgin. Might be a chore to figure out who built your boat.
I haven't bought a new boat in a long time but used to be manufacturers tested their boats with different hp outboards and could give you some idea of performance. I once bought a new Ranger Cherokee rated for a 115 and asked about the difference in performance between a 90 and a 115. The dealer...
In my opinion the tracker Grizzly is an overweight, overpriced slug. Take a look at the Lowe riveted 1648 with no center seat. Alumacraft makes a similar boat. Either would be lighter and less expensive than the tracker.
I knew I saw what you're looking for somewhere. Finally found it again. Go to DirectBoats website and look up their Waco 10' model 1432 Series Jon Boat. Lenght-10'--bottom width-32"-- weight-78 lb-- weight capacity 325 lb.-- max hp 3hp--- 47" wide. WAAAAY to little for this old guy but might be...