Fascinating . . .

I found some great links to published data:

Supernovae observed in the Milky Way

Information on the historical supernovae

A Catalogue of Galactic Supernova Remnants*

In terms of visibility, it's interesting to me that of the six plotted by the Belgian magazine, three are close to the radius drawn from here to the galactic center -- where a dilettante like me would expect more intervening dust, thus less visibility. On the other hand, the magazine's plot is two dimensional, and doesn't show offset above or below the galactic equator.

I also wonder how the potential to see Milky Way supernovae in various parts of the sky is influenced by the populaton density of stars capable of becoming supernovae.

There is another way to detect new supernovae, and approximate their direction, without being able to see them: neutrino detectors, like the ones set up to look for proton decay. SN1987a lit them up, as I recall.