You either have two choices. Sell now or commit to training him. No real in between on that.
I'd advertise him both here and the USA offsite. You just have to hope he'll catch someone's eye. Unfortunately, he's 19 and has a low salary. But it depends on his stats as to how much you'll get for him. I sold Olvera for a ton last year, but he was 18 and started with 57 TSP.