I think the definition of spam necessitates some level of bulk sending, and I struggle to consider ~fifty emails over the course of two or three years "bulk".
Here's my basic criteria for spam:
1. It's unsolicited.
2. It's trying to sell something / exploit people.
In my grading scale I classify you as a spammer. A "bespoke" spammer perhaps, but I still do not want to waste time reading anything you send me, or waste time even clicking "mark as spam", unless I ask for it. You would be stealing my mental CPU cycles (which are few and precious).
Are these synonymous?
The CAN-SPAM Act does not forbid explicitly selling something. Rather it requires an opt-out mechanism and identifiers for who the sender is.