You need to invent a US billing address - I hear the White House is rather popular - but these games are cheap as chips.
http://www.amazon.com/gp/feature.html?ref=hy-bill-dvg-1&ie=UTF8&docId=1000716161
Of note: download Stronghold Kingdoms (crappy free to play, pay to win game) for free to get Stronghold Crusader (excellent castle-building / siege game that usually costs moneys) for free.
AoE III Complete for ?6.50, http://www.amazon.com/Age-Empires-Complete-Collection-Download/dp/B00AR05D78/ref=br_lf_m_1000716161_1_28_ttl?ie=UTF8&s=videogames&pf_rd_p=1557665502&pf_rd_s=center-10&pf_rd_t=1401&pf_rd_i=1000716161&pf_rd_m=ATVPDKIKX0DER&pf_rd_r=04GM50BNYTDYE1KT33AR