The material is not there yet for 3D printing. Someone did it and the results were too heavy and too brittle. IIRC, it was
@fritzhimself.
OP-Are you looking for the pre-parallel drilled versions of the 6.1 16x18? Only a few places would possibly have them (the auction sites, the big river site, the arm-and-leg site and GSS). You could try posting in the Wanted section. Good luck because it has been at least 5-6 years since the old BLX1 6.1 versions.
There are wrg710300's available, but I cannot be sure if those are for parallel drilled or not.