Re: otasco, longlife
Can we clarify, here. Is this an electric trolling motor or gasoline? Otasco was a private brand of some Eska outboards. I can't find anything about electrics with that brand.
In any case, Otasco didn't make anything. They rebranded stuff from other manufacturers. The old all metal electric trolling motors are tough to find any parts for, I'm afraid. In some cases, you can manage to find things like seals, etc., but that's about it. Some of the really old ones actually used automotive parts for the motors. In those cases, you can often rebuild the motors.
If you can post a photo of your unit, we can probably come closer to identifying who made it. That would be a start.