You might try getting a can of spray on varnish, give the decals/labels one coat before applying to the canoe, ie while still on the printed sheet. The spray on varnish coats the ink, and should help prevent it from running when the decals are soaked or varnished over after the decal is on the canoe. It works well for me with water slide decals,the ink does not run when soaking or when applying regular spar varnish after it is on the canoe.