If the cylinders on an 04 are similar to the ones on my '99 (and the brakes are different) they will be very cheap. I replaced mine last year with OE and was pleasantly surprised how cheap they were. However, if you damage the pipes connected to them, which often happens, then they are not cheap!
Be careful how you install the new bits. There have been people who that have renewed the brakes then complained that the brakes are useless and don't self adjust - but in actual fact they have installed the parts incorrectly. One notable numptie went about 10 pages into a thread complaining and not listening to people - until he went very silent.
Good advise to to take a picture of the old setup after removing the drum, but it sounds like that might not be a suitable suggestion in your case!