You're just using wireless G, so pretty much any wireless adapter will be fine.
If you want to keep with Linksys, you can get this:
http://www.ncix.com/products/index.p...acture=Linksys
Pricematch to $48.99 here:
http://www.canadacomputers.com/index...891&cid=NT.541
Or if you wanted something cheaper, you could get this one:
http://www.ncix.com/products/index.p...cture=TRENDnet
Pricematch to $22.17 here:
http://www.swiftgamers.com/ProductDe...Code=TEW-424UB