Age gaps in those countries are on average quite similar to the west, contrary to what stupid PPBs would lead you to believe. Regular girls there are not looking for a man thats 10, 15 or 20 years older than them. Most girls date their looksmatch and age match, just as in the west.
Now you being foreigner having more status, money, exotic factor... you can get away with a larger age gap than usual, say 5-10 years, instead of 1-3 years.