If 1 pac costs $0.0004, and if Y = 10,000 pacs, then the total cost is $4.
So, after redemption by 1000: 1, the equation is:
Y pacs / 1,000 = total price / 1,000
or, 10,000 pacs / 1,000 = $4 / 1,000
or, 10 pacs = $0.004
or, 1 pac = $0.0004
So the price/value per pac will be same.
10,000 PAC x (price of) $0.0004/PAC=$4 Value
A 1:1000 reverse-split Changes 10,000 PAC to 10 $PAC (PACCASH)
So, after the 1:1000 reverse-split, the adjusted price for 1 $PAC= $4/10$PAC=
$0.4/$PAC vs
$0.0004/PAC. 
oh, right, but still depends on demand for pac in the market.