Attributes stock count

Hi, I’m selling lenses with eye powers. Each product has between 6 to 8 levels of eye power, and I would like to sell them in pairs, but for each pair customer has to pick either the same eye power for both eyes or a different eye power for each eye. I don’t want to use variations since the stock count will be at variation level, which isn’t what I’m looking for. Basically I’m looking for attributes stock count.

So I’m looking to duplicate the same set of variation on the same product page so customer can select twice. And both selections will be deducted from the same set of attributes, in this case eye powers.

Example: Imagine you want to sell 1 set of 2 t-shirts in the same design but this design comes in 10 colors, so you want your customer to select a color twice before add to cart. Can be same color or different colors. On the back end you are keeping stock of the same design in every color, each color has a different quantity. When customer buys a product on the front end, the stock of color/s bought is deducted accordingly.

I hope my explanation is clear and someone can help me achieve the above scenario. Thanks in advance!

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