You can get from Vancouver (YVR) to Denpasar, Bali (DPS) on Cathay(CX) for 42,500 British Airways Avios + $168 or 34,000 Avios + $ 288.20. There is availability on Thursday, Oct 30. Then you just need to get yourself to YVR.
To do this you need to open a BA Executive Club account (free), check BA.com for availability and transfer Amex MRs over to your new Avios account. Make sure you check award availability before transferring your MRs.