I am pretty sure you can't sponsor your parents if you do not live in Canada. So I don't think you need to talk to a lawyer.The offer I have got is to move and live in the US for at least three years. If I can not sponsor my parents, I might reconsider the offer. I think as you guys suggested I have to consult with an immigration lawyer.
Thanks.
If you already have 3 years of NOA from the previous 3 years, then stay in Canada and apply.
If you don't have 3 years of NOA, then stay and work in Canada until you have 3 years of NOA and then sponsor them while you live here.