There are 123 stacked pentahexes with a total of 615 hexagons. I think it's to hard to produce physical pieces, but
the computer can act rather easily on this set.
Here are two constructions symmetric under 60° rotation. To get a solution I split the whole construction in
two parts, which were solved separately. Click the pictures to see the layers.
A prism symmetric under 60° rotation isn't possible to construct. We have 615=5*3*41 and the cross-section might
be 15, 41 or 123. On the other hand it's impossible to divide 15, 41, 123, 14, 40 or 122 by 6 without remainder.
But a prism with triangular symmetry can be made.
Rectangular like cross-sections are also possible.