I'm not great at fundamentals or valuing companies, & this may...

I'm not great at fundamentals or valuing companies, & this may have been done on another post but I couldn't find it. So here is a laymans simplistic attempt to try and see what this stock may be worth.

The facts(all conservative to keep it real)

50M odd ounces of silver underground.
Mine life 5 years.
Recovery cost $10 / ounce
Capex of 32M.
Current market cap value of 130M.
Initial 1.8M ounces go to CBA.

Lets assume silver stays at $30 for the next 5 years.
And they mine approx. 10M ounces a year.
Earnings will be around 10M x $20 = $200M P/A
Total recovery = 5 Years x $200M = $1.0B

At a current market cap of $130M it seems pretty cheap.
P/E around 0.7 ATM ?

I don't know how to value a company so any feedback by someone more knowledgable would be appreciated.
Also, how does this compare to its peers?