Modern Africa issues - unpriced?

The stamp catalogs seem to have a hard time with some modern issues, mostly from African nations where the postal service has been erratic, or places like Afghanistan where the postal service was non-existent for most of the 1990s-2000s.  Sometimes it's easy to find cancelled-to-order or mint examples from after 1990, but we very rarely see postally used stamps from some of these places.  Much less complete covers with stamps on them.

While breaking up a collection of Malagasy Republic, it was good to see a page from after 2000.  Those are the hard-to-find items. Here are some examples of stamps that the 2023 Scott catalog could not put a value on ... there is just a dash for a price.  Here are the unpriced #1403A,f:

Then there are some where the catalog does price them but at surprisingly high values.  Here are #C200B-C, that listed for $130.

As if that's not enough to suggest how rare these stamps can be, and how difficult they ware to research or verify, here is a set of two: #1471 has a dash for a price, and the other not mentioned at all.

It's not clear what to do when there's a dash for a price.  I wouldn't just randomly guess something like $130, but out of tens of thousands of stamps I have seen from Madagascar in my 40 years in the business, I have only even seen one of the ones shown here.  So it seems reasonable to offer these at $5 to $20.  They are deftinitely a challenge.

We just listed these and others on the HipStamp store for the San Diego Philatelic Library.