I am not sure it would meet your needs but I was looking at a portable for portage lakes, canoe and ice fishing and had come to the conclusion that the Bottom Line Fishin Buddy would be a good unit to try. Doesn't seem to be the highest end stuff but should read depth and mark fish. I really like that its one box attached transducer with internal batteries, no cords. Is anyone using this unit for this purpose?

Nerdy