I changed out my glow plugs a few days ago after having a ridiculous time starting my van up on Mt. Washington last weekend...caused me to miss the powder on Sunday
. For the record I did confirm that it was the glow plugs that were the issue. Anyway I used NGK 2161, available from Lordco (and most other suppliers) for around $48 each. There are other options that are more and less money, but if you need them in a hurry...
Here a couple of things that I found out after I had changed the plugs out...I didn't have any issues but would be more cautious next time.
Changing out your glow plugs is easy and should only take about 30 minutes. One CAUTION though, do not force the old ones out. That is, if they are really tight and you have to apply a lot of force on the wrench handle to loosen STOP! It is possible to shear off the glow plug and then you are left with a real mess of trying to get a sheared glow plug out of the engine.
If they are not coming out easily try soaking them in WD-40 or something like that and allow the engine to heat up to expand the metal a bit. If the engine is warm or hot then you will have to take caution with the glow plugs once you get them out as they will be hot. I replaced mine with a cold engine and had no problems but I have seen reports of others not being so lucky. Bottom line don't force the glow plugs in or out.
-Mark