I have an Asus 9800 GT I could get rid of, it's basically an upgraded 8800 GTS so CS:S will run smooth but more graphics-intensive stuff will be a struggle on high settings. I just used it in between my 8800 GTS dying and getting a 460 so it's never been overclocked but I hear overclocking performance is best in class.
$20 is cool, if you're able to Paypal I can ship or you can pick up sometime (I live/work in Newmarket), card has a pretty low-key heatsink so that might save a bit on shipping $ but I did a quick estimate and it should be ~$10.