Build a box set in Squarespace & keeping inventory of items

Site URL: https://www.baybonbon.com/

I run a small-batch chocolate operation. Currently I offer chocolates in collections only, but in the future I would like to offer 6 signature flavors and allow customers to build their own box. For example:

Box Sizes:
6 Piece
12 Piece
24 Piece

Flavors:
Flavor 1
Flavor 2
Flavor 3
Flavor 4
Flavor 5
Flavor 6

I know that I can create a product for each box size and then have flavor variants for each space available in the chocolate box, but this doesn't allow me to track inventory accurately. Same for creating a custom form. I need to be able to track the total number of boxes vs. the number of each flavor chocolate I have available.

Does anyone have any thoughts on how I can execute this idea... perhaps a plugin or something?

Ah... thanks anyway, Paul!