Kuzych sticks to the "short" CMT listing which you will find in John Bulat's catalog but - except in one instance - he downgrades the prices to below those in Bulat - and below the prices being achieved in recent auctions (Raritan, for example). The "short" list includes only those combinations of stamp and overprint originally issued. Reprints using the original handstamps can be found on a larger range of stamp + overprint combinations - see the list in Michel, for example.
Kuzych comes in lower than Bulat because he thinks that "It is not possible to readily distinguish stamps of the original 13 values from their reprints" so the prices he gives relate to his assessment of the combined numbers of originals and reprints. In contrast, Bulat prices on the Originals and though he expertised CMT overprints, to my knowledge, he nowhere indicates how to differentiate originals and reprints
In my view it is true that for mint stamps, originals and reprints cannot be reliably distinguished except where the basic stamp + value combination is wrong.But used stamps can be differentiated and Original stamps used within the Occupation period identified. The latter are rare but if they have postmarks dated in the period of occupation from one of the offices supplied with the CMT stamps, then they are going to be Originals.
As for covers, I would be surprised if more than a few dozen non-philatelic covers exist used within the correct time period at the right offices. But they do exist - the stamps were distributed within Pokutia and were used on correspondence. In his memoir, Czerniawski indicates that he was able to colect them at the time. There are a handful of non-philatelic covers in the upcoming Corinphila sale of the Zelonka collection.
For some reason, Kuzych retains one of Bulat's high valuations: he pitches the 60h on 20 heller green with inverted overprint at $2750. Bulat has $2350 but with a note insisting on positional importance. A block of 4 showing the correct position (first stamp in the sheet based on Cerniawski's narrative account of the original issue) and expertised by Bulat sold recently for $800 before commissions in Raritan, so about half Bulat. I have never seen another example of the positional block.
Even when one lumps Reprints along with Originals, it is my experience that the stamps are scarce. I have a minimum price of 10 euro for a mint stamp in good condition. Curiously, most of the stamps one does come across are in good condition. Whether Originals or reprints, CMT overprints never made it into schoolboy collections. They were always too scarce for that.