Shopify Custom Size Option + Show Size in Cart (Budget $50 MAX)

I need a Shopify developer to add a simple “Custom Size” option on my product page (sample attached).

What I need:

Keep my current standard size variants if possible (if not, I can remove them)
When “Custom Size” is selected, show Width + Height fields (units optional)
Save the entered size to the cart/checkout as line item properties
Show a small badge/label in the cart like: “Custom: 120cm x 80cm”
No preview/visualizer

Budget:
$50 fixed. Do not apply if you need more than $50.

To apply:
Send 1–2 examples of similar Shopify work and confirm you can do it for $50.