Too many variables to give a semi accurate answer other than between $6 - $24 per acre.
If it is within 2 - 2.5 hours of major cities probably closer to the high end.
I know this, many places near big cities lease for almost unbelievable per acre prices, it is worth whatever someone is willing to pay, if that someone isn't you it will be someone else.
I also know how much $ I turn down every year to lease our place in Blanco county, truly hard to believe how much some folks would be willing to pay.
I suppose that sounds right, since I probably see about 10-20 "lease wanted" ads for every lease being offered within a reasonable drive of SA or Austin.
I think that what's driving the prices up is the fact that many landowners have gone from doing year-round leases to doing day hunts. If they can charge someone 1-1.5K for a single weekend anda couple of runty deer, they're going to want to charge 4-5x that for a season lease.