PEY to J op up is relatively easy (OK, not so easy for MPGR but there's always a chance). So you can buy PEY roundtrips HKG-NYC, which I think is around 21k HKD/30k HKD for E/R class. In addition, for R class you can upgrade using Asia Miles at a rate of around one roundtrip upgrade per 2.xx roundtrips.

Business class within the 20k-30k range is not impossible; but you will have to start from an outport, I think TPE/ICN/CAN/BKK/KUL are good candidates, in descending order. Of course, you can opt to fly HKG-DFW-LGA or HKG-LAX-JFK with AA, the latter which I think is a good idea with good timing, product and lounge options.