You think you need a regex? You're not sure if it really requires a regex?
I'll make it clear for you and fulfill your need in a feasible way. I'd be the first one to tell you if you're choosing regex where you should not.
Just send me a message explaining your need. I'll have a look and we can fix a rate that's feasible for both. In most cases, I can provide you a sample delivery also. You can order afterwards.