A few months back I had noticed a tiny amount of oil on my belly pan, and it seems to have gotten worse. While I was installing my heating pads I looked around, and discovered my timing chain tensioner's gasket has apparently failed.
The part numbers for gasket and filter are 14511PHM003 and 14515PHM004, which came to about $20 shipped from G1parts.
Also, I failed in acquiring NEXT oil, so I resorted to ordering Honda's Green Oil from a UK dealer. This oil is close to a 20 weight when warm, but much thinner than a 0w16 when cold, so going off of those two numbers, it's an ideal replacement for my engine. Cost was about $50 shipped from Cox motors, and it arrived in 2 days. I plan to do an early oil change after I fix my oil leak.