Yes if it was me i would replace it. Your already going to have alot of the major components off for a timing belt change so it would make sense to. Plus if i has never had one being an 04 with 70k i would, and also because the added load your going to be putting on everything.
2004 Focus SVT Vortech Boosted
1994 Thunderbird Cobra motor swap w/ N2o
2006 Subaru WRX Stage 2
1995 F150, for when nothing else runs