Depends on what you want and why??
No one in there right mind would be out on today's roads playing bumper tags with a "Real Cobra" anyway so forget that!
That said your first step with a "Kit" as always is do your research! And a good start would be this book. :
https://www.amazon.com/BIG-Guide-Cobra-Kits-Parts/dp/0970117930
And for what it's worth if I was going to get a Cobra Replica and had the budget it would be a "Superformance Cobra." Nuff Said there.
A big block Cobra ... looks freaking awesome, it did back then and it still does now! If that is what you want, then that is what you should get, end of story! But if this rather expensive piece of gear is gonna more that a "Garage Queen" in a stable of uh more "practical vehicles??" Then perhaps there are better options?? But bottom line, nothing carries more visceral impact, than a "Big Block/Motor" with a lopey cam ... taking care of business! In the "sound fast" category ... that is always gonna win!
But if "speed" is the thing and can you actually put "power down" a Big Block Cobra ... LOL "Good Luck" with that!
In the "real world" day in day out 0 to 60, is what matters. And there pretty much hands down no "BS" ... a factory stock Tesla S .. is the top "Dawg!"
Now admittedly boring by comparison, but as it happens you already "own" a car from the manufacture you need! If your goal is "Speed" and a car you could actually drive on wet roads??
A "Subby" WRX! Get a low mileage example and take it to a "Subby Tuner!" It would take less than 20 grand in mods! And if ... speed is is your thing and driving a car that "won't try to "KILL YOU!" is important, a modded WRX, would put a "Beat Down On" a Big Block Cobra! And if the roads happen to be wet?? That is "Game Over!"
But hey a heavily modded WRX, does not sound or look like a Big Block Cobra! You did not say what your "car guy" background was??
Aww well regardless, best advise with your choice is well don't drive it in the rain, and on dry ... make sure the steering wheel is pointed where you want to go before dropping the hammer cuz you know ... barring "counter steering" that is where your heading, "Good Luck" with your choice.