To follow-up... I ordered the knockoff Meade AutoStar #505 cable and USB to RS-232 Serial Adapter from AstroGadgets.com
. The shipping cost (~$5) was reasonable and the items were delivered in a few days. Thus far, I'm quite pleased with both products. The knockoff Meade AutoStar #505 cable is 25' long and appears to be well-made. The USB to RS-232 Serial Adapter works great. The adapter uses a FTDI chip; providing driver support for Windows, Mac, and Linux. As an added bonus, the light on the USB to RS-232 Serial Adapter glows red.
Thus far, I've used both items to update my #497 AutoStar hand controller's firmware and control my telescope (Meade DSX-125AT) via laptop (Cartes du Ciel).