Classic Japanese.
Early Celica, RX-3 or4, C10 Skyline, 240Z, Subaru 360, even a Datsun Sunny.
Those at least have a chance of being made (since Tomy has no interest in US cars). Only US car I’d like to see (that Tomy have a chance of making) would be a Viper.
For Euro cars, I’d love a Lancia Stratos or Delta.
A Shelby Cobra isn’t a Mustang. The Mustang is a Shelby 500.