I paid to have scanned the two best non-tourist maps available in the print collection – both are declassified US defense maps:
United States. Defense Mapping Agency. Hydrographic/Topographic Center. Cambodia city maps 1:25,000.
Phnum Pénh / prepared and published by the Defense Mapping Agency. Hydrographic/Topographic Center, Bethesda, Md.
[Bethesda, Md.] : Reprinted by NIMA, 2001.
Scale 1:25,000 ; transverse Mercator proj. (E 104°49ʹ15ʺ–E 104°57ʹ16.1ʺ/N 11°36ʹ37.03ʺ–N 11°31ʹ07.05ʺ).
Hollis Record. Full size JPG.
And this one from a series map available at Pusey. Full size JPG.