Or T20
.
These are Olympus flashes, by the way.
You might find that the T32 and T310 are a bit big though. One of the legion of smaller Vivitar or Sunpak flashes might work better, because of their size and shape.
Although the Guide Number system works well, you may wish to consider a flash that offers auto exposure Thyristor circuitry as well, because for shorter distances, the flash can be set to recycle more quickly, and give many more flashes per set of batteries.
EDIT: For film, I would recommend Kodak Elitechrome, or E100G