Montana de Oro being a State Park you have to camp in the camp grounds, which are a bit back from the beach, no dispersed camping.
Pismo Beach is the only camp on the sand, beach camping in California and its just down the road from SLO. Pismo can get very busy and noisy because of all the people on the dunes. There are other small state park camp grounds in the area.
Going north from Morro Bay is a state park right on the beach just a few miles up hwy1 I believe it is now Morro Strand state beach or park. I know it as Atascadero beach but I maybe wrong it has been awhile since I have been there. Maybe it’s time I go home just on a trip
Montana de Oro is a great place but you must camo in the appointed campsites, there is very little open camping in that area.
Jalama Beach County Park is GREAT, if you can get into it. It's south of Lompoc off of Highway 1 in the middle of nowhere.