Specialised South African Catalogue

Was wondering if anybody out there can help me on this. I am looking for a particular catalogue of South African stamps which may be out of print, and to be honest I am not 100% sure of its existence.
I am currently using the South African Stamp Colour Catalogue which is a very good piece of referance, but I believe that there is another catalogue (or there was) detailing flaws, variations and errors in great detail. (It was not published by any of the major philatelic publishers. I have on occasion asked some collectors in SA and some dealers for that matter but no help from there, in fact most didn't even reply. I have seen listings which show definite flaws and varieties which must have been sourced from somewhere, I have heard of a so-called 'HANDBOOK' but I always come up against a brick wall.
Would be extremely gratefull for any help on this as it would mean finally getting started on sorting out about 50 000 SA stamps that have been sitting in patiently in their boxes for the last 30 years

Yes, that would be the Handbook Catalogue, which has had a variety of formal titles and editors (Hagger, Kaplan...) over the decades.

There are also some other specialty catalogs, such as "A Collector's Guide to the Pictorial Definitives of the Union of South Africa 1926-1954" by Baker.

Thanks khj, much appreciated, at least now I know what I'm looking for

Here's an interesting link that may be helpful: http://www.southafricacollector.com

jogil thanks for the link, its an amazing site,I'm sure that I will be a regular visitor there