Yeah, they could do a better job by having a big button directing people to buy it at the website, but if you go to the "Buy" option in the top bar you'll find it among all of their other offerings.
€1100 with the current F39 release discount and €1000 with the extra €100 discount for Fedora contributors
And it's thanks to the work of those people that it has finally made it upstream, specially Fedora's Martin Stránský (who has been doing tons of work on Firefox, including making Fedora the first distro to ship Firefox with VA-API enabled by default).