Snipe,
I have used wooden SKIDS as platform for tree stands and they are very strong.
You just have to nail two proper lengths of 2x6 to the side of 2 good size trees and set the Skids in between. You can also cut them in half dividing the bottom and upper side to make 2 platforms.
Next is making a ladder that you can take on and off the stand so people won't just use it when you are not there.