Affordable SIM card options for a family trip to Tokyo in November?

Hey fellow travelers! I'm a mom of two planning a family trip to Tokyo this November to enjoy the autumn leaves. I want to make sure we stay connected while exploring the city. Could you recommend budget-friendly SIM card options for our smartphones that provide good coverage and data for mapping our way around? I'm looking to keep our communication costs under $100 for the whole trip. Any tips on where to buy them in Tokyo or at the airport upon arrival? Thanks in advance for your help!