44/64" diameter = 17.4625 mm diameter
If you cannot find a wood dowel of that dimension, then just do as you proposed, by inserting a 44 ring cigar into the trough of the mat, then adjust it so that the mat is snug, and maintains reasonable tension over the arc of the Lieberman.
Bob
If you cannot find a wood dowel of that dimension, then just do as you proposed, by inserting a 44 ring cigar into the trough of the mat, then adjust it so that the mat is snug, and maintains reasonable tension over the arc of the Lieberman.
Bob