It appears one can hack the ePub to change font settings and include an embedded TrueType font (maybe also other formats?), and the Kobo firmware will successfully process this.
I'm waiting for the battery to finish charging to see how Proggy Tiny Slashed-Zero looks. It may be too small, in which case I'll try one of the other Proggy variants, or Dina. (Both Proggy and Dina have TrueType implementations, although I'm uncertain how complete they are. I may have to look around for a better choice of a small-format fixed width font implemented in TrueType format.)
I'm waiting for the battery to finish charging to see how Proggy Tiny Slashed-Zero looks. It may be too small, in which case I'll try one of the other Proggy variants, or Dina. (Both Proggy and Dina have TrueType implementations, although I'm uncertain how complete they are. I may have to look around for a better choice of a small-format fixed width font implemented in TrueType format.)