I couldn't find these, either in windows.inc or MSDN, so this is from the C header (wingdi.h I think). I'm not even going to pretend like I know how to convert it correctly, or even assume that it should even be in there at all.
* field selection bits */
#define DM_ORIENTATION 0x00000001L
#define DM_PAPERSIZE 0x00000002L
#define DM_PAPERLENGTH 0x00000004L
#define DM_PAPERWIDTH 0x00000008L
#define DM_SCALE 0x00000010L
#if(WINVER >= 0x0500)
#define DM_POSITION 0x00000020L
#define DM_NUP 0x00000040L
#endif /* WINVER >= 0x0500 */
#if(WINVER >= 0x0501)
#define DM_DISPLAYORIENTATION 0x00000080L
#endif /* WINVER >= 0x0501 */
#define DM_COPIES 0x00000100L
#define DM_DEFAULTSOURCE 0x00000200L
#define DM_PRINTQUALITY 0x00000400L
#define DM_COLOR 0x00000800L
#define DM_DUPLEX 0x00001000L
#define DM_YRESOLUTION 0x00002000L
#define DM_TTOPTION 0x00004000L
#define DM_COLLATE 0x00008000L
#define DM_FORMNAME 0x00010000L
#define DM_LOGPIXELS 0x00020000L
#define DM_BITSPERPEL 0x00040000L
#define DM_PELSWIDTH 0x00080000L
#define DM_PELSHEIGHT 0x00100000L
#define DM_DISPLAYFLAGS 0x00200000L
#define DM_DISPLAYFREQUENCY 0x00400000L
#if(WINVER >= 0x0400)
#define DM_ICMMETHOD 0x00800000L
#define DM_ICMINTENT 0x01000000L
#define DM_MEDIATYPE 0x02000000L
#define DM_DITHERTYPE 0x04000000L
#define DM_PANNINGWIDTH 0x08000000L
#define DM_PANNINGHEIGHT 0x10000000L
#endif /* WINVER >= 0x0400 */
#if(WINVER >= 0x0501)
#define DM_DISPLAYFIXEDOUTPUT 0x20000000L
#endif /* WINVER >= 0x0501 */
They convert like this.
DM_ORIENTATION equ 00000001h
DM_PAPERSIZE equ 00000002h
DM_PAPERLENGTH equ 00000004h
DM_PAPERWIDTH equ 00000008h
DM_SCALE equ 00000010h
DM_POSITION equ 00000020h
DM_NUP equ 00000040h
DM_DISPLAYORIENTATION equ 00000080h
DM_COPIES equ 00000100h
DM_DEFAULTSOURCE equ 00000200h
DM_PRINTQUALITY equ 00000400h
DM_COLOR equ 00000800h
DM_DUPLEX equ 00001000h
DM_YRESOLUTION equ 00002000h
DM_TTOPTION equ 00004000h
DM_COLLATE equ 00008000h
DM_FORMNAME equ 00010000h
DM_LOGPIXELS equ 00020000h
DM_BITSPERPEL equ 00040000h
DM_PELSWIDTH equ 00080000h
DM_PELSHEIGHT equ 00100000h
DM_DISPLAYFLAGS equ 00200000h
DM_DISPLAYFREQUENCY equ 00400000h
DM_ICMMETHOD equ 00800000h
DM_ICMINTENT equ 01000000h
DM_MEDIATYPE equ 02000000h
DM_DITHERTYPE equ 04000000h
DM_PANNINGWIDTH equ 08000000h
DM_PANNINGHEIGHT equ 10000000h
DM_DISPLAYFIXEDOUTPUT equ 20000000h