Sure mate. All you have to do is tell them that you lived in Canada for awhile, thats why you spell things funny: like colour. Then, buy some chewing gum and put a wad in your mouth before speaking and ..presto, you have a Yank accent.

Im sure you can find something. There are schools in Japan that specialize in limey-talk. I remember that when I taught in Europe, it was difficult for me to compete with the Brits. I worked hard to adopt a Brit accent and even did the CELTA at a British school. Alas, I was too old to train. But even though you Brits have the market locked-in over the Atlantic pond, I still found a job. But that EU requirement is far more stringent than a Korean hagwon requiring a certain accent.

Cheers and good luck :-)