You will probably be able to buy an AV8B in a few years time when the USMC get their F35s and it might be possible to get support from Boeing.
OTOH you would almost certainly have to keep it N-registered in the experimental class which means keeping it in the USA.
Not much chance of getting an ex-US mil AV8B.
US Govt/Mil are making it VERY difficult to get more modern ex-mil jets on N-reg. Why do think Art Nalls has a ex-RN SHAR.
Even the Collings Foundation were recently thwarted in trying to aquire the last non-cut F-105 Thunderchief from Davis-Monthan as they didn't want it being returned to the air, despite CF's already successful operation of it's A4 and F4.
And further more, as of a couple of weeks ago, the FAA released a memo relating to regarding further restrictions on granting airworthiness certs for ex-mil jet aircraft.