What to use instead of Deprecated GetFNum in OS X SDK 10.8

What to use instead of Deprecated GetFNum in OS X SDK 10.8

I have the following code, which I want to convert from MacOS SDK 10.6 to
SDK 10.8:
short theFontNum;
Str255 fontType = "Helvetica";
::GetFNum(fontType, &theFontNum);
::SetMenuFont (newMenu, theFontNum, 11);
GetFNum is deprecated in SDK 10.8. Can someone suggest what can I use
instead?
Thanks!