The DirecWay dish can be used for FTA and the LNB is most likely good (LNBs rarely go bad). I believe the HTS receiver you are referring to is an analog receiver, and will be of limited use since most FTA is now digital. It wouldn't be used to move a small dish like the DirecWay, but rather one of the older BUDs (8-10 foot dishes) that used linear actuators. You'll want to pick up a digital DVB receiver to be able to watch most FTA channels. Only DirecTV receivers will work with the flex port, so that will be of no use.
Intamin, you wouldn't happen to be a roller coaster enthusiast, would you? I ask because Intamin is a coaster designer and manufacturer

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EDIT: The DirecWay dish you have pictured has a strange LNB/feedhorn combo... It appears that the LNB may be specialized, perhaps Ka-Band, but I'm not sure. If it is, you will need to replace it with a standard Ku-Band LNB, and do a bit of retro-fitting.