Calrose, the primary rice grown in California is a Japonica, its just Japanese rice grown in America. Tamanishiki, which is one of the high grade sushi rices is grown in the US and Japan

It is O. s. subsp. japonica

Costco sells a couple of Kokuho-brand Calrose varieties, which are decent drop-ins for for generic East Asian rice.

haven't seen japonica often in the US, but jasmine rice is similar and available pretty much everywhere.

in fact, jasmine rice smells and tastes better, and stickier!