Bud's has 2 long guns in 45ACP that are CA compliant, however, they are both out of stock right now. budsgunshop.com/search.php/type/Firearms_Long+Guns/exclusive/ca/caliber/10000572

No rifle listed, but the CA compliance info for rifles is as follows
"✘ Semi-automatic centerfire rifles ​with a fixed magazine​that exceeds 10 rounds. ✘ Semi-automatic centerfire rifles that have an overall length of less than 30”. If the stock is collapsible or foldable, the measurement is taken from the collapsed or folded position. ✘ Semi-automatic centerfire rifles that do not have a fixed magazine, but have any ​one​of the following features: ✘ Complete AR lower receivers may not include prohibited features listed above, nor appear as a named item on Appendices A, B, or C (see​“Rifle Flowchart”​link above). ○Pistol grip - a grip that protrudes conspicuously beneath the action of the firearm. ○Thumbhole stock ○Folding or telescoping stock ○Grenade or flare launcher ○Flash suppressor or flash hider ○Foregrip - a grip that the barrel and in front of the action"
Full info here
budsgunshop.com/feeds/state_reg/california_restrictions.pdf

Ping Keung, no long gun specified. Buds two CA compliant .45ACP long guns are out of stock : budsgunshop.com/search.php/type/Firearms_Long+Guns/exclusive/ca/caliber/10000572