Would this be it?
https://www.amazon.com/UCMM-Mazda-Navigation-System-Canada/dp/B07P4DZY7B/ref=sr_1_8?crid=VESBDKU0ADZA&keywords=mazda+3+navigation+sd+card&qid=1563806195&s=gateway&sprefix=mazda+3+navigation%2Caps%2C143&sr=8-8