Are you open to importing them in? You can always go straight to the source and ask someone like Hermanus (his FB page is Betta4Ever) if he has any. Many of my wilds have come from his fishroom and the health and quality of his stock is superb.
Otherwise, are you a member of the IBC Species Maintenance Program FB page? That should hook you up with a lot of wild betta breeders/keepers in the states. Maybe someone will have some channoides.
Not a lot to tell you the truth. They both get to about the same max size and habitat. Care is pretty much the same as well. They each have a slightly different shade of red. The channoides doesn't have the black coloring in the dorsal fin and that is the most distinctive difference.