Product review (4 stars): This works, but you can use-off-the-shelf too
I ordered this OEM for the cooktop light in my microwave/hood.  Tomorrow being a big cooking day (Christmas), I thought I'd also see if I could find it locally after ordering this one.  The Blue Big Box Store didn't have the exact "part number", but I found the same bulb in the lighting section.  It's a G4 base, 20W, 12V bulb.  This particular one is made by "Utilitech" and their part # is 0181120.  Works just fine- even seems a little brighter than the original (there's two bulbs side-by-side in my hood, so it's an easy comparison).  The price was just about the same,  so if you're got prime and the time, easier to order this one.  But if it's the day before a major cooking day, you can easily find a replacement if you're near a Big Box store, or probably any hardware/electrical supplies store.  Just get the specs right.

One note- I misunderestimated how hard you have to push this in (at least in my fixture) and it kept falling out.  One I gave it a good shove, it stayed fast.  the base of the bulb was then against the fixture with none of the leg exposed.