This may be tough to find. Leberl lived through several changes of nation (Bohemia - Czechoslovakia - Germany - West Germany) and through WW2. I recall reading that he lost a lot of his work as a result of the war and was kind of dispirited afterwards.
I'd imagine that finding most scores of his would necessitate looking into German and Czech repositories and libraries at a minimum.
The Deutsch Nationalbibliothek has the following in their catalog:
https://portal.dnb.de/opac.htm?method=s ... =119267101
A little of Leberl's work was published by Chanterelle (op.46 and op.48), and there's that Naxos 2-CD set, which is also by Fabian Hinsche, who recorded the version you heard on the radio program. Alle-noten has a few scores but not op.62.