Rossler/Rosetti viola concerto in G: there's a new score of the work
(1999) out from Amadeus-Verlag edited by Chris Walton (Winterthur,
Switzerland, a major publisher of lesser-known music who have also
published major scores by e.g.  Robert Fuchs...).  The notes in the
catalog entry claim that it was edited from library manuscript, so there
may not be any recordings (and I am having difficulty finding any...)

-Eric Schissel