[tecleandor]

Most expensive thing will be the switch, the cabling is not that expensive.

For a 10g card to work you'll need a pair of SFP+ transceivers, one for the card, and another one for the other element you're connecting to (a switch, a router, another computer...) This transceiver can be chosen for copper or fiber depending on your needs, and each transceiver will be from 50 to 100$. Then you buy fiber or copper Cat6a cable.

But, if your two devices are near (less than 10 meters), you can use a Twin Axial DAC (Direct Attach Cable) : you won't need the transceivers, you can just directly connect the two devices with this cable into the SFP+ port, and it's kind of cheap, for example, 12€ a 3meter run:

https://www.fs.com/en/products/40141.html?currency=EUR