They cost 40 bucks for a set.
www.hardtopguy.com
They require more than just a few tools. You have to drop the oilpan, reinstalling it requires gasket material. Getting at the bolt under the #1 cylinder appears to be a bitch because the oil pump is in the way. Some people have used a flexible driver tool to get at it. Apparently, some engines in Europe failed after the bolt was incorrectly installed in the #1 spot. (Guess even Honda mechanics need to practice on someone's car
)
Anyway, if you haven't done stuff like change your own oil, tranny fluid, brake pads etc I wouldn't try this.