Generally speaking, Red and White oak have similar properties. And on a boat you dry sail you could get away with red oak. The different grain structures between the two shouldn't be an issue. They both fasten and finish well. The big issues as I understand are white oak bends better when green or when steamed and white oak is greatly rot resistant which red oak is not. I think red oak will discolor from water more readily but as I said on dry sailed boat this shouldn't be an issue. As long as you pull the boat after each use and wipe down the bright work that is.
I think white ash is a better substitute for white oak especially on smaller boats. White ash will wander a bit while straight grained white oak stays pretty straight.
There are some strict traditionalistas who will tell you what I said is bunk regarding wooden boats but thats just opinion. If this is going on a Kyak and you can keep ahead of the maintenance, I say use the wood you have and enjoy the water.