I'm getting about $1.2B ($6/share).

This is how I arrived at this valuation:

PV in 43-101 given their assumptions: $540M

I compared the resource price (after $US-$CAN exchange) between the 43-101 and the most recent investor presentation. Using the sensitivities from the 43-101, I estimate that the change in resource price should account for about a 37% increase in the PV.

I compared the grade of resource between the 43-101 and the most recent investor presentation. As grade increases the mine produces a larger quantity of nickle without incuring significant additional costs (i.e. more revenue with even costs). I have therefore made the assumption that an increase in grade would have a similar impact as an increase in the price of the resource. Increase in grade should account for about another 25% in PV.

I compared the amount of resource between the 43-101 and the most recent investor presentation. There is an additional 9M tonnes of 1.1% nickel (inferred). Just ratioing shows that we have about 55% more nickel than at the 43-101 (11*1.64%+9*1.1%)/(11*1.64%)-1 = 55%. Note that this excludes the impact of increased grade as it was already captured above. I assume that this 55% extra nickel will be as profitable to mine as the average nickel in the 43-101 (i.e the reduced revenue due to lower grade is offset by the fact that there are no additional CapEx costs)

$540M * (137%) * (125%) + $540M * 55% = $1.2B

Given 200M o/s shares: $6/share.

This $6/share will be split between us, and the company who takes us out.