Can't you unplug your router to connect your modem directly to your computer, just for that..? Also, I found this:
http://forums.battle.net/thread.html?to .... sid=5000#0
The first post there seems to be mirroring all the patches. Also, found this advice further down the thread:
"For those of you having technical difficulties manually patching.
1) There is a folder under your SC2 beta folder ( where the game installed ) that will be named "Updates"
2) If you are missing the folder named "Updates" then that means you can either copy the file named updates that comes with the .zip files on maged's site OR you can start the blizzard downloader and it will automatically make one for you.
3) for every patch that you DO NOT ALREADY HAVE you need to put those files into the "Updates" folder.
4) When you run the installer it should start the starcraft 2 beta blizzard downloader, which will verify and patch your game right there in the same screen.
5) If it does not patch correctly you have another problem, or are missing the proper files in the Updates folder.
The reason this is so complicated is because blizzard is testing their patch delivery as well.... They don't really want you to use mirror, or make it easy. "