I just know, that you can have smaller intrrvalls (hours, days, weeks) with LNVPN.net

You could try this. It’s per hour and payment via Lightning.

No experience with them myself though:

https://lnvpn.net

You need nostr:npub1zzt0d0s2f4lsanpd7nkjep5r79p7ljq7aw37eek64hf0ef6v0mxqgwljrv tech for that

Not quite but https://www.mysteriumdark.com/

Bytes are not scarce. But bandwidth over time is scarce.