From that second picture you posted, you can see the throttle, arm coming off the carb, so yes, it is throttled. I have one with this setup. They throttle pretty well and idle descent considering they are designed to run WOT all the time; it does take a little bit to get the mixtures set right though. The carb they usually put on those have 9mm bores, while the stock venturi they come with are 11mm, so there is probably a slight power loss. (I have the venturi that came with it too, but have never used it.) These engines HAUL!
I paid about $225 for my setup with the engine/pipe/carb combo brand new. That should give you an idea what yours is worth. Hope you enjoy your GRRT!
Carl