Optionality plays in a PM bull market

Clearly at present most PM stocks are doing well due to the rising price of the underlying metals. Those producers with the best free cash flow are generally doing the best in terms of SP at present. However, I imagine that at higher sustained metal prices some latent deposits may become economical and really overdrive the SP as they come online - is there a sleeping dragon amongst the majors waiting to explode?

Given the last 5 yrears of harsh bear environment there may well be deposits that have fallen off the radar of investors simply because the economics of the project were so dire.

For those of you who are truly bullish on gold, which Asx companies do you think have the best optionality plays???(read: large uneconomical deposits at today's prices ~$1340USD - but highly economical at a higher PoG/PoS)

We can probably divide responses into two groups and price points to stimulate discussion:

1. best optionality producers at a bullish $1450USD & a BULLISH $1900 USD price point

2. best optionality explorer at a bullish $1450USD & a BULLISH $1900 USD price point

cheers in advance!