At this point in time, this may not be viable, due to lack of interest in HD radio.
Not to get too far off the WNSR topic, but people trying to sell HD radios, should work with these immigrant program producers where the effort could be a real win-win. Immigrant's who don't speak English tend to congregate in certain neighborhoods. Big store displays touting local radio programs in their own language could sell a lot of HD radios.
Years ago, I had an old friend who owned an Italian language station broadcasting on an FM subcarrier, and knew another guy who did very well broadcasting the same way in Mandarin for the Chinese community. Both guys just made an effort to sell or lease subcarrier receivers at various locations and at public gatherings that attracted members of those immigrant communities.
Both guys claimed to be making money, and were able to make their programming available to their audiences 24/7, instead of leasing an hour at a time on an AM. This is actually a way to generate interest in HD radio.