I have not launched in Campbell River, but I have driven into the marina area there. Launch ramp looked OK, I didn't inquire about parking but there appeared to be plenty, not sure of the security, but I think it is about as close to Octopus Islands as you will get. Sayward would be an option, but they were not particularly "user friendly" by phone.
I have used the BC Ferry the last 2 summers and it's a good choice. You would either have a ferry to get to Lund or to Campbell River. The Tswassen to Duke Point (Nanaimo) runs discount fares during the summer, on certain days and times (a tourism promotion for Vancouver Island) and it is worth using ( ~50% off, for oversize, over length vehicles.) Be prepared to travel early, but you could easily leave from the Ferry launch and have your boat in the water and be at Octopus Islands on the same day. You will want to check the Seymour Narrows current/tides before transiting that stretch.
Another option would be Pacific Playground, on the Oyster River. It is a bit farther south, a doable launch ramp, (be careful about tide levels as you don't want to be launching or retrieving at a low tide, but they have good parking, and a wash down area after retrieving.
Browns Bay has fuel, and a restaurant with pretty good fish and chips, but their launch ramp does not have a side dock (at least when I was there in 2015), so launching was a 2 person affair at least.
Harvey
SleepyC :moon
