Probably not, there is limit and it will probably sold out weeks ago. Either shuttle or buy early, otherwise no permit needed on weekdays.
Yes they sell day passes at the parking lot
Yes, there is a pay station. Show up really early if you don't want to shuttle.
You cannot buy a pass at the trailhead, they can either be reserved in advance online or you HAVE to take the shuttle and will earn your pass that way. Even if there is space in the lot unless you reserve room they will ask you for your pass or tell you to shuttle in. Due to the fires in the Gorge their trail has been extra busy.
if there is space in the lot
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