I'm with Tako; I've never heard of dumbbell eyes being considered illegal on a fly in fly-only waters. If it's part of the dressing, it's kosher. I've fished a fair bit in BC, and it's never been an issue for me.
As far as most steelhead waters being fly-only, I would say otherwise. A fair number now have bait bans, but most are open to other types of gear (spoons, yarn, etc.). The Cowichan is the only fly-only stream I can think of off the top of my head. So, unless you guys will be hitting that river, I don't think it will be an issue for you either way.