Those don't seem to be available in the Netherlands
. The only anti-nosebleed things I could find were a sort of caps you can stuff in your nose to stop the bleeding. Luckily the nosebleeds are at the back of my nose and since I sleep on my back the blood runs into my throat.
I was thinking that since it happens mostly at night and the bleeding happens at the back of my nose/top of my throat it might be caused by how I breathe through my nose at night (combined with colder air).