This is a popular question.
Check out this link
http://www.catsailor.com/forums/showfla ... #Post29758
At that site, if you do a search on righting systems etc you'll find lots of very thoughtful answers to your question. Everything from Righting poles to Soloright to shroud extenders to righting bags. You name it. Homemade ones and manufactured, whatever your taste.
Having said this I was told by a dealer that he carries a trash bag (the big orange ones for leaves, so you have extra bag to grab hold of) in his pocket when he goes sailing. Voila, cheap,
easy to find, you can do your research to decide if you like that system. 