Well, Steve, it's a good
thought that the OP coin might be from Elymais
but, given the apparent lack of an anchor
motif behind the bust
, I'd be inclined to think it's a Parthian chalkous
. And, given the rectangular shaped beard and diadem loop and ends, I suspect it has to be one of the following: Artabanos II, Artabanos III, Gotarzes II, or Vologases IV. There could be more possibilities among the chalkoi, but I'm no expert on them. Perhaps Alwin or Schatz may chime in.
Abcoin, although it can be a tedious process, your best course of action may be to search
on the term "Parthia chalkous
" at coinproject.com
and scan through the results. Best wishes.