All kidding aside, we really haven't come up with a good answer to the OP's question: What is a Merry Widow pool cue?
I did a bit of googling and learned that an operetta, by Franz Lehar, entitled: Merry Widow, was popular back in the day, but in itself had no reference to pool, or pool cues.
The most telling bit of research may be a design for a corselet, a smaller and more basic version of a corset, that was popular in the early 1900's. In the 1950's the corselet design was reintroduced and named after the operetta, Merry Widow.
Although unsubstantiated, my guess is the Merry Widow cue is simply a plain cue with a wrap, just as the Merry Widow corselet was a plain undergarment wrap for a woman.
I have to go lay down now, I've got a headache from this shit. :smile: