You can replace your stock timing sprockets (gears) without a problem. Always replace all three pieces (cam sprocket, crank sprocket and timing chain) as a set. I'm not sure I'd reuse an old set, unless they were very low mile and tight (no slack). Timing sets aren't crazy expensive and its a job you only want to do once.
If you are buying a new timing set, here are your choices:
1. The stock timing set uses a silent link type chain (also called a "Morse" chain). They work well and also use a small chain tensioner which rides against the outside of the chain. There is no adjustability of cam timing with a stock timing set.
2. A stock design timing set sold by TA Performance. The sprockets are billet steel and have several keyways cut into the crank sprocket for adjustability of cam timing. This is also a silent chain and you can use the stock chain tensioner.
3. A double roller style chain. This is a stronger chain (not really needed for a stock cam). They usually have at least 3 keyways in the crank sprocket for adjustability. Do not use the stock tensioner with a roller chain. There are several suppliers of good sets (Cloyes, Rollmaster, and Progear come to mind).
While you are doing this work, remember to drop the oil pan and clean it out. The little bits of the old plastic gear end up in the oil pan and get sucked up into the oil pump pickup tube.
A new oil pump pickup tube is a good idea. You might also consider blue printing the front cover/oil pump. (I'm good at spending other people's money!!!)
DR
Its been a PIA getting mine rebuilt due to a local builders error. Still waiting for him to do the right thing and repair his mistake.
