Capturecards

With the current situation more and more video conferencing is being done.
My system at home that I use for work however has no webcam.

I do however have a nice sony alpha 7 which I could use but I need a capture card.

Does anyone have ideas for capture cards that are well supported and don’t cost an arm and a leg?

I saw the elgato camlink 4k but that one requires a work-around outside of obs apparently.

I was in the same boat but went a slightly different route. I’m using my android phone instead with software called droidcam. I didn’t have to buy anything.