Bud's has the OD XD9 for $398, but no OD 40's.
They have the black XD40 for $426.
Of course, there's a $20-25 shipping charge on top of that. Then you gotta pay your FFL dealer his transfer fee. So they're not quite as cheap as they sound.
I don't think the OD guns have ever been very big sellers and probably don't get imported very often. If all the OD 40's are sold out, it may be awhile before more are available. Call or e-mail SA and ask them about availability.
I have an OD XD40 which I've nicknamed "the frogger". It's butt ugly but shoots really well.