You can get it here
http://tardis.tiny-vps.com/aarm/packages/o/openssh/openssh-7.4p1-2-arm.pkg.tar.xz
However rolling openssl-cryptodev back to 1.0 (if you need to ) isn't that simple. pacman -U seems to have a problem with this. You would need to extract libssl and libcrypto from the package in cache.