I know of two good researchers who can obtainrecords from Arad for you. One of them is willing to do smaller jobs. Obtaining records from Romania without a researcher is very difficult. Almost no records from Romania have been microfilmed by the LDS, so you can't go that route, either.
I would recommend making a list of everything you need from the archive so the researcher can do it all at once. It will not cost much more than sending them out in search of a single document.