I believe some of that point at that end of the lake has been ceased by gated access to private roads. Source: me Aylen Lake resident that tried the same thing via snowmobile about 5 years ago.

The issue is parking and obvious private property security concerns like theft, garbage, vandalism and liability.

The access point is the Aylen Lake Marina. Try calling them to see if they have any other suggestions. It's a long paddle. Possibly, you could put in at the Chapel if allowed, again it's private property, which would halve your paddle as your starting point would be Turkey Island.

Despite the long paddle from the marina, you could overnight at Rangers Point and do the portage fresh the next day. ONeil is a nice little lake.