before you consider Team-C Venum 427, Take a look at the Backdraft Racing product. A while back they were the same product from one company. After a parting, Team-C basically took the original car and duplicated it exactly in another factory. Everything was identical except for the brand of paint. Backdraft has since improved the design somewhat in its gen II product. Team-C is still gen I if I'm not mistaken. Backdraft has improved the hood shock, trunk prop, the steering shaft mounting, re-positioned the roll bar and added support for the seat belts, widened the rear about an inch so the larger wheels/tires would fit properly, and a few more little things that I'm probably missing.
If you are looking for Big Block power, I don't think either Backdraft or Team-C are set up for that.
Superformance is still tops for the S. African factory Turn-Key minus offering. Shelby is next to produce cars in S. Africa (stay Tuned). Kirkham can still top them all if you want Aluminum coachwork and computerized fit and finish. This is actually better than the original, but it is still not an original. Back to Superformance, it may be better than the other S. African products, but to me personally, it is not $10K better. (Nicer wheels, more authentic in ways, but I'll use the $10K on the drivetrain).
If I had your perceived budget, I would probably shop for a finished car that is for sale private party. In that $45K to $65K range are some mighty fine cars and no wait!
Good luck with your journey.