Camping is allowed on MOST beaches in Oregon outside city limits and NOT fronting State Parks, however, I would not recommend it! Tides vary greatly and the highest tides are usually at night this time of year, therefore you could set up camp high and dry and end up with a rude awakening in the middle of the night. Rising ocean levels and beach erosion have really amplified this!
You posted this on the Reedsport Forum. Is that your destination or are you open to other areas of the coast?
Also, please keep in mind that oceanfront property is *private property* if there are houses around. People can and do call the Sheriff if they see people camping in their "front yards".