2 of those were built, one was for sale a couple of years ago, the other one is rotting away in Tallinn, parked in a garden next to a Estonia 21 wreck and some other old soviet cars. It is rear engined, with ZAZ powerplant and glassfibre body. If I recall correctly, there was a capacity limit for road-going self-built cars in USSR, it was probably about 1 litre. That's why ZAZ engine had to be used, all the other passenger car engines in USSR were atleast 1,2-litres or larger. Kalle Keel was chief designer in TARK, but I think this car was more like his private project, than a prototype for the Estonia factory - it was hard to buy a car in Soviet Union, so some people decided to make their own cars. I'm not kidding.
I haven't got any articles about it so I don't know more details.