kirita bay would be a good option,

Plenty of places up there to drop a yak in the water, just drive along the coast until you find a place with access, depending on how close you want to get to Wilsons bay, Kereta boat ramp has good parking. Most beaches will be stoney or you might have to carry your yak down over some rocks.

If you want to hit the farms, they are closed to the shore from the Waikawa end and good fishing pretty much close in all way along the coast, surf casters have been doing well.

The few times I've fished Wilsons, cars park up on the stony beach & the kayaks head out from there. Unsure how high the tide gets when they park up on the beach, but I am sure you can gather that info at the bait shops along the road before you get to Thames
At times you will see rock fishers to the right of the bay, they do good at times
The main channel is a short paddle out, lots of weed structure in close & a mussel farm close by.... some really good fish come out of there & along that coastline in close
Plan your tides correctly as the current can rip thru there

Kirita bay is private with a doz or so batch / houses on site.
If you have a motorhome / caravan, you can go next door at Kirita bay & stay with the Fosters.
The fishing would be 5min paddle. Looking out to sea from Kirita bay, theres a mussel farm to the right of the bay & more mussel farms as you head north, nothing in the middle of the bay & good shallow water fishing to the left of the bay
Any easterly breeze is best as it will be off shore.... good luck

Google - Wilsons bay fishing, some good info already posted