" ARIN's free pool of IPv4 address space was depleted on 24 September 2015. "
Since there are no more, you can only try to buy them from those that own such. I expect this to run in the millions if not more USD.
We have been trying to find how to get a hold of a class B ARIN block. Needless to say, ARIN is not giving them out anymore. Can anyone recommend where to get one?

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