First of all you do know its a Tri-Stage paint ?
Why dont you call the shop that sprayed the inside of your vehicle and get the color code & paint product they used, be easier doing it that way.

And l will just repeat whay Biskit said.
Any Auto Paint jobber has the formula and can mix as much as you need, it will requier a white base, and the pearl top coat, then cleared. Each coat of pearl you lay down over the white will get muddy and yellow. so dont think laying several coats of pearl will be better, it wont !

Plus if it ever gets damaged later on its not an easy repair.

Good luck on your paint project.........

SprayTech