There IS another way to get a SimRay other than being a Scientist. I think it might be new with the Seasons expansion, though. There's a computer interaction called "Purchase Gift..." which allows you to buy all sorts of odd and rare items to use as gifts. One such item is the SimRay. Though, without the Science career, you still can't upgrade it with new functions.
On a side note, I think it's really stupid that you lose the ability to do Science stuff if you quit the Science career (for instance, to pursue other careers for the Renaissance Sim aspiration), so you can't use the Invention Constructor to make or upgrade devices anymore, and you can't use the Chemistry Lab either. It's not like someone would just forget how to do their job, just because they resigned. No other career has this ridiculous effect and I really hope they patch it sometime.