uh, the only sites i can suggest as alternatives would be
CDJapan or
Amazon Japan if you can navigate it.
you could also run a google search looking for import video game shops, or check local hobby shops if there are any in your area, to see if they either have the soundtrack in stock or will search for you (some stores do offer those kinds of services).
and if none of those work, there's always ebay.
my guess is that the soundtrack is out of print. if that's the case, it's possible that the
only way you could get a copy of it now is through ebay.
hope that helps!