This would be suitable, for example (I also find the price/performance very good here):
Lian-Li PCIe x16 riser ribbon cable - PCIe 4.0 (20 cm)
On the subject of cooling I have to disappoint you, with the vertical mount ("set up in the case") the cooling is much worse, because the fans of the card are usually much too close to the side panel and thus the airflow is blocked. It just looks nicer, but that's it. (Source:
https://appuals.com/mounting-g...)