I was looking for some standard PHP function to replace some value of an array with other, but surprisingly I haven\'t found any, so I have to write my own:
Depending whether it's the value, the key or both you want to find and replace on you could do something like this:
$array = json_decode( str_replace( $replace, $with, json_encode( $array ) ), true );
I'm not saying this is the most efficient or elegant, but nice and simple.