It is similar to should of, but I've seen that many times before. Been/being is a new one on me.
While I'm here, I remember a thread ages ago about 'another thing/think coming'. It really threw me as I've always thought of it as 'another thing coming' but if you think about it, logically it has to be 'think'. Anyway, a columnist used 'another think coming' in a newspaper the other day and it still made me stop and read it again. I wonder how long it takes to retrain your brain with things like that.