Yes: Commonwealth Fusion essentially is buying the world's supply of it.

MRIs are a more mature market, i.e. > 1 units, and need to justify component switches not just for feasibility, but for profitability. Swapping out a known-good for something in such short supply isn't feasible, it's more expensive than liquid helium.

Source: https://spectrum.ieee.org/fusion-2662267312 "Over two years, the team managed to buy up most of the world’s supply of 4-millimeter-wide HTS tape"