It is possible, but you'd need enough patience/time and money to do so...
An imported vehicle would have to comply with either US or Canadian safety/bumper regulations and US or California emissions standards in order to be imported (unless it is a show/display car or for racing, or allowed by the Dept. of State for foreign armed forces or diplomats), as the Supra is not in the list of other non-conforming vehicles. Here are the rules for importing into the US, as well as a list of registered importers (who'll modify the car to make it legal in the US):
http://www.nhtsa.dot.gov/CARS/RULES/IMPORT/
(you may want to contact a few of these importers to get some idea of pricing)
see also:
http://www.epa.gov/otaq/imports/
http://www.epa.gov/OMSWWW/cert.htm
http://www.dmv.ca.gov/pubs/brochures...cts/ffvr29.htm
http://www.cbp.gov/linkhandler/cgov/...ortingacar.doc
http://www.cbp.gov/xp/cgov/travel/cl...utomobiles.xml
http://www.cbp.gov/xp/cgov/trade/bas...orting_car.xml
http://www.cbp.gov/linkhandler/cgov/...s.ctt/iius.pdf
Duty due on the vehicle is likely to be about 2.5percent of what you paid for it.
The customs import bond is likely to be at least the vehicle purchase price, plus 1.5x the vehicle purchase price to the DOT, while waiting for the vehicle to be brought into compliance.
Some other related articles that may help you:
http://foreignborn.com/visas_imm/ent...ingyourcar.htm
http://www.importexporthelp.com/importing-cars.htm
can you import a toyota supra from the UK?
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