Add fast 1Mbit or 2Mbit SRAM to Adafruit itsy-bitsy M4

Hello friends

I have a very basic knowledge of electronics, I'd love to get help from professionals. I'm working on a project in arduino environment, the board is Adafruit itsy-bitsy M4 Express featuring ATSAMD51 32-bit Cortex M4 core running at 120 MHz,512 KB flash, 192 KB RAM.

https://www.adafruit.com/product/3800

I want to add to the board FAST 1Mbit or 2Mbit SRAM memory (NO flash), the chip as to be very small and very fast, support SPI) The price is...

Add fast 1Mbit or 2Mbit SRAM to Adafruit itsy-bitsy M4