replacing all timing chain rails requires R&R the front timing cover. As long as you have the timing chain out you may as well replace w/ a new one and be done with that for another 200K+ miles
A new water pump maybe if the old one looks crummy (it has to come off to get the timing cover off) and a new belt tensioner would be recommended.
If the vac pump on the engine doesn't have 4 torque head bolts on the cover by all means get the new version which will not come apart like the old ones and destroy the engine.
I would keep the existing oil pump, they are very long lived. Some say to replace the chain that drives it however, I didn't on my 603 rebuild.