[OFFER] Windows NT 4.0 Service Pack 6a (High-Encryption for Server)
This wasn't exactly hard to find (just through the wayback machine), but it's worth noting that there are separate versions for "high-encryption" version of NT 4.0, i.e. the server versions. I have this, happy to submit it.
Windows NT 4.0 Service Pack 6a (High-Encryption) for x86