If you have a GPU with a native HDMI out - you can pickup a standard 50ft HDMI cable. If not and your card can pass audio through HDMI via a DVI to HDMI adapter (which many can), just use the dongle (only a couple bucks).
I see the HDMI 1.3 50' cables for $18.75 and ~$22 for the 1.4 shipped from ebay.
There really is no reason to spend $68 on that cable.