It really depends what your goal is. None of the resins are even close to simulating the various properties of 6061.
Rigid 10K is the stiffest material, but if you look at the datasheet values, it’s still like 6x or 7x less stiff than 6061.
Elongation and impact strength will be substantially worse.
In this type of scenario, you really should be just using any resin to test fit, and then moving to CNC the part out of 6061 for functional testing.
I’m assuming the geometry is simple since it’s a bike clamp. Also, I wouldn’t consider metal 3d printing unless you have wild geometry…its almost always more expensive than CNCing a simple part.