You can not give an address outside Canada to receive your PR card.
If you give an address of a person in Canada who is supposed to receive it for you, you need to make sure this person is trustworthy. In addition, the immigration officer may ask you if you plan to be at this address when the PR cards arrive. If you say no, they may decide to withhold them until you back to stay.
You would have to find out from the Canadian embassy in your home country how long it takes them to issue a travel document so you can apply in time for your return trip. From what I have heard, they are usually valid for 6 months but you can ask about that too.
Arriving with a travel document instead of a PR card should not pose a problem. As more than 6 months will have passed from your landing, you will not get your PR card mailed to you as you could have on your first landing. Instead, you will have to apply for one, get new photos and pay $50 processing fee. The current processing time is around 5 months and you will have to pick it up at your local CIC office. You can find the application forms here:
http://www.cic.gc.ca/english/information/applications/prcard.asp