Great thanks RJ.
Well I just got back from the post office and things didnt go as smooth as I hoped. First, anyone that sent a SASE with American stamps, they werent worth the paper they were printed on. Canada Post only accepts Canadian postage stamps, for postage. For anyone participating in Canadian hosted swaps, you should use the universal postage coupons as a couple guys did, for return postage. Second, any containers over 23mm (not sure of the conversion) had to be sent at a more expensive rate. If it was over 23mm, it cost around $4CAN and if it was under in was $1.70CAN. So anyway I covered all the costs (about $13CAN plus all the universal postage coupons I had received (6x $1.75US, I hope you guys dont mind me using them), hoping the favour would be returned one day if need be. I hope everyone enjoys their flies, I certainly will.
PS- If you did put stamps on an envelope they could still be good to use if you can get them off.