I've dealt with both autograph requests and ebay sales in canada and what i've found with autograph requests you can use an IRC or you can include a couple u.s. dollars however i have seen where if you write to someone in canada that is near the u.s. border or who often travels to the u.s. they will use your u.s. postage and mail it back to you when entering the u.s. most canadian ebay sellers will not exept u.s. money orders unless they have a way to cash them and prefer paypal or canadian currency. I have several friends in nova scotia and at times get canadian postage from them when really needed which isn't too often.