You wont find many sleeping bags good to 30dF at 2#. I returned a montbell #7 (50dF) bag in exchange. It weighed 1#15oz and its one of the best and most comfortable bags made.
I am a side sleeper and a quilt is a good option or at least worth a try.
Rectangular bags have too much room and dont hug your torso enough to be efficient. That said you can build a quilt, or have one built that can open up into a flat quilt, or used like a mummy on top with a footbox. You really want a foot box in cold weather IMO.
My tester quilt just has a very simple velcroed vertical footbox and its very comfortable. It works better for me than a drawstring type.
Another option that might work for you is a semi rectangular sleeping bag good to 30dF or a lighter bag with a liner.
Like a 45dF semi rectangular bag and a 50Df quilt liner, similar to the one I linked. At least that is what I am doing, but my setup will be a 25dF down outer bag, and a 50dF cuben climasheild 10 oz quilt. That should be good to 5-10dF and weigh 2#9oz.
As others have mentioned this is a good option for $200
http://www.mountainhardwear.com/Product.aspx?top=1831&prod=2611&cat=1890&viewAll=False
You could also get a pounder plus (2# in mummy form) and cut the hood off, but its a bit overrated. Actually good to 32dF I think. There is one for sale on the gear swap forum.