Part Number Based Inventory Control

Hello,

We have many products where a single part number spans multiple variations and sometimes multiple pages and I am looking for a way to automatically update inventory on every variation/page the part number is listed on.

For example PartNumberX is listed on PageA and PageB. I have 5 in inventory so both pages are inventory controlled and set to 5. A customer purchases PartNumberX from PageA. PageA now has 4 marked in stock yet PageB still has 5 marked in stock. I would like the inventory of PartNumberX on PageB to also be automatically updated when PartNumberX is purchased from PageA.

Is there a way to do this? A plugin perhaps.

Thank you