Looks like I found the material closest to a “Pro” level bachi properties. It is a Polyetherimide (PEI) polymer. Material comes in different sheet thickness: 0,8mm, 1mm, 2mm, 3mm etc, semi-clear, amber color. I have seen black version as well. I have been playing with two pieces of 1mm PEI glued together as I did not have correct thickness material laying around. I compared it to “classic” bekko or faux bekko bachies for hardness, flexibility, wear, bending force, “springy” feeling and it seems to be a really good match. It is expensive, way more expensive than acrylic (but not as bekko bachi ) and a bit fragile (close to acrylic, maybe a bit less). I would say it is overpriced a lot due a popularity of this material as a bead material in 3D printers.
I have ordered a 3mm thick piece and going to build a test bachi as soon as I receive the material.
Just curious if anybody tried it as well.