I would say sit for the exam again not only because of the 2.0 point difference but also because your score may put you aside from competitive CRS (I'm not sure about the other factors of your PR application such as # Yrs of Experience, education, age, etc..).
From your post, currently, you're in CLB 10 for listening, CLB 9 for Reading but CLB 8 for both W&S. Even with re-marking, you're highly unlikely to get more than 1 band increase in Speaking and/or Writing. So I'd say, think carefully! I believe you will do better if you sit for another exam given that you already have attempted the test once and your results are not bad for a first attempt honestly, there is still room for improvement on your IELTS performance.
At the end, your decision would also depend on your current CRS with your current IELTS marks; does the current score make your profile competitive enough? (ie. above 440 CRS) If so, you don't need to worry about re-marking or sitting for the exam again.