If this was a 10-20 dollar item, I would buy it. Doing tinkering with serial ports to USB is a pain. And then trying to figure out which com port you are on…ugh. No kit for this solution, but the author does provide the info to build it yourself.
http://blog.avishorp.me/2012/12/wig2012-entry-xser.html#!/2012/12/wig2012-entry-xser.html