It looks like anything with a CAN interface is out of stock these days, which is why you are out of luck. This is not surprising, actually, I suppose car manufacturers have picked up all the existing stock of anything having a CAN interface. This is just dumb hoarding on a massive scale, but that's what we have to deal with.
As a last resort so that your project doesn't remain stalled, perhaps you could temporarily use another STM32F4 chip (e.g. STM32F411) and use 3 separate SPI to CAN interface chips with some "glue code"? And when supplies of the STM32F413 MCU normalize, just remove the superfluous code?