There are no public prices and you need to email some company for more details. With most businesses this means you contact a salesperson who will play an extended game of "how much you got?" and the pricing AND the level of service provided will vary widely depending upon your negotiating power.
The dearth of information about this 'product' sold by a 3rd party suggests something shady is probably going on.
>The paper is written by economists and not technologists, and so there is no mention of CDNs or web caches
Caching is a pretty poor excuse. Caches can be invalidated. And CDN basically means caching by another name.
It makes much more sense (both economically and technically) that they simply crippled the free feed. Especially since it is provided by a private third party who makes bank on the people who purchase the premium edition.