Between $3.10 and $3.75
Allowing for the $15M to be paid in all stock, you first have to set the price of the stock. I use $0.20, $0.30 and $0.40 to get my target prices. I think $0.40 is fair because of the warrants that are already out there and we'll be trading at that price this week.
I use $0.20 as the floor since that was basically where we were trading -- that's an absolute giveaway floor price, tho. I think $0.30 should be the rock-bottom.
At those valuations, you give 75M, 50M and 37.5M shares, respectively, so the outstanding doesn't jump near as much as feared. Instead it goes to somewhere between 225 and 187.5M
Using 7x revenue (another valuation estimate), the final calculation is just dividing 700M by each outstanding share number to get $3.11, $3.5 and $3.733, respectively.
Hang on -- we'll probably blow past $4 / share.