For reference, 0.8 light years is about 50,000 AU. (AU = the distance from the Earth to the Sun.) Pluto is about 49 AU away.
This also gives you some idea of how tiny parallax[1] is. Parallax to Alpha Centauri is equivalent to looking at something four miles away and moving your head two inches. This is where the parsec comes from. If moving 1 AU causes an object to have an arc-second of parallax, that means it's 3.26 light-years away. An arc-second is a tiny angle. There are 360 degrees in a circle, 60 arc-minutes in a degree, and 60 arc-seconds in an arc-minute. To give you another point of reference, an arc-minute would be about an inch separation at 100 yards. Current instruments can use parallax to measure distances up to 300 light-years. The Gaia mission should be able to measure angles as small as 20 millionths of an arc-second.[2]
I remember some people a while back playing with the idea that the practical way for humanity to colonize the stars was by very gradually "rock-hopping through the Oort cloud", as opposed to "One Giant Leap" approaches like generation ships or crossing our fingers and desperately hoping for hyperdrive.
I don't know that we have enough information about how the size of Oort-like clouds would relate to other observable cahracteristics of stars to have a reasonable basis for any conclusion about the size of "Oort clouds" of other nearby star systems.