You can ask, but if no one replies, they probably can't tell you anything more. In fact, the fact it is a king/a
horse is not obvious from just looking at it, so you know better than most. I do
hope someone can tell you more, but have a little patience, minor
celtic coinage must really be an esoteric
field. With a little luck someone might be able to tell you something.
Some things to possibly consider.
Is there a particular die orientation? Some coins have a particular, both dies up orientation, or one die up, one die down. die orientation is probably more important where you have a coin of a kind that typically has a die orientation, but a coin you are looking at doesn't. Bad sign. I kind of doubt that
celts bothered with die orientation, but you might check.
As an
obol the coin should be silver, particular
weight is significant. You might be able to conclude that it is a silver coin of a particular
weight that would make it an
obol (or
diobol, or
hemiobol,) on "such an such" a
standard. If you can figure out the
standard, you might be able to figure out the mints that use that
standard.) something like that can be plausible for Greek, I am not sure it is plausible for
celtic.
Of course chances are whatever tribe made them could have used the
types for more than one
denomination. You can look at the
types and see if you find them elsewhere, then plausibly deduce that yours is a (possibly unpublished) fractional of those.
Kind Regards,
John