I have that same guitar, and put a K&K Pure Western Mini in it. Only mod is to replace the strap pin so it can act as a jack as well. You'll be surprised how much bass this little guitar pumps out. I also bought the K&K belt clip preamp, but keep it on the floor with a few other pedals. For volume, either get you a volume pedal, or pick up one of the Taylor guitar cables that has a volume control built into the jack that plugs into your guitar. They work like a charm.
K&K? But...I thought he said he wanted a soundhole p.u.??
Measure the soundhole. Most are about 4". If yours is smaller check with different manufacturers for their dimensional specs. I like the Bill Lawrence p.u. for it's "acoustic" sound. Fishman is popular, too.