I'd probably put an extension of Article 50 and a second referendum at about 70%

[Monty92]

Couple of issues there:

a/ There is no public appetite for a second referendum - and absolutely none among Tory voters.
b/ A tory leadership that extends Article 50 and brings in a second referendum will effectively be committing political suicide at the next election - if (and this is not as easy as it sounds) it can actually command a majority for doing so.

I know, but ultimately I think Tory MPs outside the ERG would sooner get behind a second ref than a No Deal Brexit.

It's possible that a No Deal Brexit could wipe out the Tories at the next GE, too. Even if an orderly No Deal departure was at a certain point possible, it does seem likely that it hasn't been adequately prepared for, and the economic impact would be substantial.
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