Below is the NOVA III by Tarheel Industries of Tarboro, better known to us for their Project SWORD US copies.
It's one of three NOVA's that formed the series pictured belows: I, II and III: II being a pink Thunderbird 3 lookalike and I a green jet similar to the Spacex HAWK.
The blog covered the origin of NOVA III earlier in 2009, which you can read
here and on the Space 1999 Forum
here. In short, its THUNDERBIRD 6 or at least one Brains' designs - the red craft at the bottom of the picture below. I don't think the other two designs were ever made as toys. Or?
You can see footage of Brains trashing his Thunderbird 6/ Nova III in the film Thunderbird 6 on You Tube! (about 7.7 minutes in)
Did Brains create any other craft that never made it into the Tracy hanger?