The OpenBSD net/tor -current port is correctly on 0.4.7.7, but the -stable port is still on 0.4.6.10.
I submitted a diff to update -stable port to 0.4.7.7 last week, but it has not been committed yet.
https://marc.info/?l=openbsd-ports&m=165179875418235&w=2
It's attached and should work fine.
In order to update the OpenBSD -stable port you need an updated -stable 7.1 ports tree, then you apply the patch within the /usr/ports/net/tor port, and build from there.
I can provide more guidance if necessary, but in order to not bore everyone else, maybe the Tor-BSD list is more appropriate?
https://lists.nycbug.org:8443/mailman/listinfo/tor-bsd
I can send out an amd64 -stable package, but then you'd have to trust me.
g