Wow, it came out on July 22nd?
I don't remember what specific day I bought it, but it was within 2 weeks. I know I'd had it for a while before a friend's sister's birthday on August 8th, so Aug. 5th at the latest though I already had a bunch of subsectors and characters so it was probably at least a week earlier (I was working multiple jobs over summer, so spare time was limited.)
And I remember it had to compete with the Elf II computer I assembled in June (I do remember writing pieces of a subsector generation program, but 256 bytes of RAM and a dual digit hex display made it user-hostile.)
I had no idea I was in quite that early, though I remember the shopkeeper mentioning he thought of me as soon as he saw it listed (I would buy any SF game--I cleaned everything with a spaceship on it out of his bargain box.) Despite my lack of discrimination then, this is the one I still play now.