I have found myself using the word 非中国人 to express what Chinese people would call 外国人 or 老外.
How do Chinese people feel about this word ?
Just to confirm I am using it with Chinese people.
Here are some examples of 非中国人 in place of 外国人 just to give you a feel for it in use.
住在北京的非中国人越来越多
会说中文的非中国人不是很少
你有非中国的朋友吗 ?