I am not sure what you are calling an armrest, but my 02 does not have an armrest, at least, I would not call it one. It seems more like a compartment with a cover. I had a local upholstery shop make up an insert with a matching material that I slip between the seats to get the "armrest feel" that I am looking for. There is an aftermarket armrest available at:
http://www.lextasy.com/is300_leather_arm_rest_1307_prd1.htm