This is a Mercedes place, so it probably would help more to focus on the brand of musclecar you would like, then search the net for enthusiast forums specializing in that marque, and ask there.
If for example, it was a Ford Mustang, you could try
www.Californiaspecial.com and while they only focus on the 1968 Mustang GT/CS and HCS model, they could point you in the right direction.
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1991 560 SEC AMG, 199k <---- 300 hp 10:1 ECE euro HV ...
1995 E 420, 170k "The Red Plum" (sold)
2015 BMW 535i xdrive awd
Stage 1 DINAN, 6k, <----364 hp
1967 Mercury Cougar, 49k
2013 Jaguar XF, 20k <----340 hp Supercharged, All Wheel Drive
(sold)