Galvanized will last longer, less brittle, more flexible. Don't know the length but Tony Cesare makes great, trouble free cables to length. wbav@beeline-online.net
I can't help you with the length as my cub has stock trim, but you might want to check the pulleys and make sure none are seized to the bushings. The trim cable in my cub frayed and jammed because of seized pulleys. I couldn't believe how smooth the trim operates after the fix.