McFayden Seeds is where I got mine, way back when I was in Canada. They might ship to Tahiti (they don't ship to Ecuador), and they definitely do ship to the US and Canada. Other than this, you might try a local garden centre (a good one, not a Lowe's or Home Depot) or find somebody that's already growing comfrey and ask for a bit of root. It will (naturally) come faster from root than from seed.
