Since you are going on a PR visa, you may want to get a one way plane ticket. One of the problems I found was that many airlines would not give you a decent price on a one way ticket. Air Canada, Lufthansa, and KLM all had pricing for one way tickets that was higher than a return flight!!
Don't know if this will be of any help to you, but I did find that Aerosvit, LOT, and Austrian all had good pricing for one way tickets. About half the return ticket price plus a 10 or 20% premium.