Free Custom RPZ Feeds?

[#1]

We've been using Infoblox DNS Firewall for years now, but recently our RPZ updates started failing. It turns out that although we are licensed for the DNS firewall feature, we do not have a subscription to the Infoblox thread feeds. We're not really sure when the licensing model changed in that you have to subscribe to the feeds separately, but it is what it is I guess. We're waiting on a BloxOne Essentials quote to see if we can afford to purchase a subscription to the feeds, but in case it's out of our price range, are there any reputable, free RPZ feeds that we could subscribe to? If so, are there any tutorials on how to set these up?