There are better ways to level =/
Lets say he can't afford the Dex gears, or the finer gears. Easy enough.
Go Turn Undead.
A good suggested TU build includes Turn Undead 10, Gloria 5, and Magnificat 5. Anything else is optional, skill wise. Go wild there.
Stats for a TU priest would be High int, High Dex, some luck, in that order. TU doesn't have a slow cast time, but if you need to, stat more dex than int when starting.
Experiment, play around! You might find the most awesome stats! Its not a hugely gear dependent build! Starting gears, pick up a Int weapon. Evil Bone Wand, Arc Wand[2], w/e, you don't need Instant.
Leveling wise, Start out at prison. Pick off the monsters near people, etc. Easy levleing. Once you get comfortable with it, you can then move on to either Glast Hiem Churchyard, or if you have fly wings and a good heal, Ancient Mummies.