It's safe to assume the ships we see currently are
not the only ships that exist in the Elite galaxy.
In the game's text there are casual references to a heavily-armoured "military Asp MK 2", specially-adapted Anacondas that can launch Sidewinders, and the Panther Clipper (which admittedly, has been "coming soon" for about 7 years).
According to GalNet, Narwhal Liners were in service until at least 3302, when
the remaining Narwhal serving as Spaceship One was retired, but it's reasonable to suspect that privately-owned Narwhals may still be in service somewhere. GalNet articles have also described huge
automated mining robots which, while not ships per se, are capable of flying and navigating independently, and we would realistically expect to encounter these from time-to-time as part of the "ship" traffic around extraction sites, etc.
And while we're looking beyond ships in the classical sense, presumably
something more substantial than a limpet is involved in building and maintaining the exterior of a station, constructing megaships, and so forth. There are official images, used in-game (GalNet, again), that depict
Exopods active around capital ship docks, so these proposed mini-ships are supposed to exist in the galaxy and this is seemingly just one of their uses.
Of slightly more questionable validity are ships mentioned in official ED fiction including the Merlin and Krait Lightspeeder. These may or may not be considered "canon", but either way it highlights the probability that these and other older, out-of-production ships would likely still exist in limited numbers among collectors and in backwater systems... excepting some headcanon-y dragnet recall of every obsolete ship in every star system in the galaxy... which... why?
There's also no reason that the other ships hinted at in-and-around the game are the only ones that might be imagined to exist without us encountering them.