UCC28700 Flyback transformer selection

Hi,

  I'm designing the AC/DC converter. The output is 5 V and 10 W maximum. Given the equation from the datasheet, I found that the transformer should have ~500 uH, 13-15 Nps (Primary to Secondary turns ratio) and ~3 Nas (Auxiliary to Secondary turns ratio). I couldn't found the appropriate transformer from DigiKey/Mouser. Does anyone has suggestion about the transformer which might fit to my application?

Thanks!

Ye-sheng