That is a big challenge my friend. The good news is that there are many Fiero owners on this forum that if and when you find one, can help check out the car for you. According to my calculation your budget is $10,800 US dollars. That might be a bit on the low end for a kit car this rare but depending on condition it may be doable. Several hundred Miras were made and you might want to look into that car as a fallback position. You will be faced with a huge shipping costs to Great Britain that I would inquire about before moving forward.
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" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "