The first task is to obtain written permission from the author of the font. I have asked some authors before and been given gracious permission by all but a single author. So please contact the author.

What may complicate the issue is the author has created a "Pro" set of that font that I suspect has a full set of glyphs.

In any case, you will need a font editor to make the composite glyph or a discreet one. If you get the permission and a font editor, we can walk you through how to go about this.

Take care, Mike