We would like to add folding doors between our kitchen/living room. There is currently an opening around 152cm with a door frame. I've been looking at standard internal bifold sizes and most seem to be either slightly too large or too small for the existing opening. Would widening/narrowing the opening by a couple of cm even be a possibility?

Also a bit stuck with where to start on this. What trade should we talk to - is it likely to be a builder, carpenter or someone else job?