Sebastian was later acquired by Sheldon, which continued to produce only the gearhead models and you can find some more documentation on them searching for Sheldon.
However, your description of the lathe as "light duty", points me to guess that the lathe your friend bough is one of their cone-head machines.
If I recall correctly, at a certain point they acquired the license to produce one or two models of lathes discontinued from another company (I don't remember if Leblond, Monarch, or something else). You should find more on this in other threads.
Since, in the early days, they produced mostly treadle lathes, a few pictures of the lathe your friend bought would help understanding what he got, in order to give you more relevant info.
Paolo
