I find the newly observed properties to be interesting and hope that they lead to a deeper understanding of superconductivity in general.

Does anyone know how difficult/expensive it is to get something that cold?

It seems like it would be virtually infeasible, but I really have no idea.

In terms of costs your thresholds are the boiling points of nitrogen (77K, surprisingly cheap and easy to deal with, even for a hobbyist) and helium (33K, more expensive,scarce, requires more energy to condense). To get lower than that, you need your own cryogenic cascade as I doubt you can easily buy something as ridiculously dangerous as liquid hydrogen (boiling point of 4K, explosive in contact with oxygen).

At less than 2K I think that the only merits of this discovery are theoretical.

I don't think that anyone believes that superconductors below nitrogen temperature have any viability outside the lab.

You mixed up the temperatures for hydrogen and helium.

Thanks!

liquid hydrogen safety https://www.youtube.com/watch?v=7bFJK5kU_UQ

[it doesn't explode on contact with air]

It doesn't directly answer your question, but you might find this interesting: http://omegataupodcast.net/285-superconductivity/

It's below the condensation temperature of helium, so they probably cool it by evaporating liquid helium. Sample volume, existing kit, helium recycling loops are going to vastly change the price structure of that experiment.