the CIA apparently did get some soviet titanium alloy for the SR-71, but most was made by US companies after they figured out how to reproduce the alloy (Ti-13V-11Cr-3Al). This is what most of the skin was made of. The engines used a different alloy for the first stage blades (8-1-1 I think). It probably had 6-4 alloy for bulkheads.
Titanium Metals Corp I know made it and probably the old Crucible metals too.
The alloy is hardly ever made anymore, replaced by slightly easier to make alloys.
there is a ukranian company called Unicraft that makes limited runs of resin model airplanes, mostly 1/72 scale. they have a model of this airplance, but not inexpensive