The owners of famed 24-hour Greek restaurant Stalactites in Melbourne's CBD have bought two Jimmy Grants souvlaki outlets that were once part of the George Calombaris food empire.

Time has run out, however, for several more restaurants that couldn't find buyers.

Outlets at the Emporium shopping centre in Melbourne's CBD and in Fitzroy were sold on Thursday to an operator with a "background in Greek cuisine" by KordaMentha, which has been handling the sales after Made Establishment collapsed into voluntary administration last week.

Sources told The Age that the prospective buyer is the Stalactites Group, owner of Lonsdale Street institution Stalactites and the takeaway restaurant Hella Good.

The two sites are set to continue serving souvlakis under the Hella Good name, joining the first outlet, which opened in Elizabeth Street in 2016.