I like my OR compression sacks. They make a big range of them in different weights and waterproofness most use the same material as your BA tent fly (70 dernier rip stop nylon). My 1 degree down bag fits nicely in a 10.6 litre dry sack with a little room to spare. The tent would probably fit in a 10L bag as well as long as its rolled nicely (the footprint might not fit though). I don't think you'll need a dry sack for the tent though. Whats wrong with the one that came with it? You could always trim it down a bit if you want to compress it more and save some money.
The bags on this page are nice:
http://www.mec.ca/Products/product_l...=1177802127853