I usually don't replace the o rings unless I have to on the filter cover. New o rings are harder to keep in place, so it just becomes more hassle.
The drain bolt has a washer that's supposed to be replaced as well as an o ring. The washer deforms a bit when you tighten it down, so lately I've been replacing it every time just to get a better feel for getting it tight. It would tough-to-impossible to get the washer off without damaging the o ring, so it will need to be done as well.
I get them from RMATV, along with tusk filters. They also have a tusk brand washer as well. I buy a few at a time of each, that way the minimum shipping charge doesn't offset the value. Also, keep the filter o rings on hand, even if you don't change them. It'd suck to miss a ride over a waiting on a $2 o ring.
Also consider keeping an extra air filter on hand. Those can be gotten from Amazon cheaply, but make sure it's a genuine Honda filter and not some cheap garbage. Honda ones also come pre-oiled, but
i DO NOT like whatever oil honda uses these days, as it seems to pass a bit of dust. Could be the amount of oil too. If it were mine, I'd get a new Honda air filter, clean it, and then use a quality foam air filter oil (which means NOT K&N oil) like Maxima to retreat it. Then keep it at the ready, since people tend to be "surprised" when they check the air filter, and you won't be caught off guard. Check it often.