These should all be available to use:
{
{"TAB", K_TAB, "#str_07018"},
{"ENTER", K_ENTER, "#str_07019"},
{"ESCAPE", K_ESCAPE, "#str_07020"},
{"SPACE", K_SPACE, "#str_07021"},
{"BACKSPACE", K_BACKSPACE, "#str_07022"},
{"UPARROW", K_UPARROW, "#str_07023"},
{"DOWNARROW", K_DOWNARROW, "#str_07024"},
{"LEFTARROW", K_LEFTARROW, "#str_07025"},
{"RIGHTARROW", K_RIGHTARROW, "#str_07026"},
{"ALT", K_ALT, "#str_07027"},
{"RIGHTALT", K_RIGHT_ALT, "#str_07193"},
{"CTRL", K_CTRL, "#str_07028"},
{"SHIFT", K_SHIFT, "#str_07029"},
{"LWIN", K_LWIN, "#str_07030"},
{"RWIN", K_RWIN, "#str_07031"},
{"MENU", K_MENU, "#str_07032"},
{"COMMAND", K_COMMAND, "#str_07033"},
{"CAPSLOCK", K_CAPSLOCK, "#str_07034"},
{"SCROLL", K_SCROLL, "#str_07035"},
{"PRINTSCREEN", K_PRINT_SCR, "#str_07179"},
{"F1", K_F1, "#str_07036"},
{"F2", K_F2, "#str_07037"},
{"F3", K_F3, "#str_07038"},
{"F4", K_F4, "#str_07039"},
{"F5", K_F5, "#str_07040"},
{"F6", K_F6, "#str_07041"},
{"F7", K_F7, "#str_07042"},
{"F8", K_F8, "#str_07043"},
{"F9", K_F9, "#str_07044"},
{"F10", K_F10, "#str_07045"},
{"F11", K_F11, "#str_07046"},
{"F12", K_F12, "#str_07047"},
{"INS", K_INS, "#str_07048"},
{"DEL", K_DEL, "#str_07049"},
{"PGDN", K_PGDN, "#str_07050"},
{"PGUP", K_PGUP, "#str_07051"},
{"HOME", K_HOME, "#str_07052"},
{"END", K_END, "#str_07053"},
{"MOUSE1", K_MOUSE1, "#str_07054"},
{"MOUSE2", K_MOUSE2, "#str_07055"},
{"MOUSE3", K_MOUSE3, "#str_07056"},
{"MOUSE4", K_MOUSE4, "#str_07057"},
{"MOUSE5", K_MOUSE5, "#str_07058"},
{"MOUSE6", K_MOUSE6, "#str_07059"},
{"MOUSE7", K_MOUSE7, "#str_07060"},
{"MOUSE8", K_MOUSE8, "#str_07061"},
{"MWHEELUP", K_MWHEELUP, "#str_07131"},
{"MWHEELDOWN", K_MWHEELDOWN, "#str_07132"},
{"JOY1", K_JOY1, "#str_07062"},
{"JOY2", K_JOY2, "#str_07063"},
{"JOY3", K_JOY3, "#str_07064"},
{"JOY4", K_JOY4, "#str_07065"},
{"JOY5", K_JOY5, "#str_07066"},
{"JOY6", K_JOY6, "#str_07067"},
{"JOY7", K_JOY7, "#str_07068"},
{"JOY8", K_JOY8, "#str_07069"},
{"JOY9", K_JOY9, "#str_07070"},
{"JOY10", K_JOY10, "#str_07071"},
{"JOY11", K_JOY11, "#str_07072"},
{"JOY12", K_JOY12, "#str_07073"},
{"JOY13", K_JOY13, "#str_07074"},
{"JOY14", K_JOY14, "#str_07075"},
{"JOY15", K_JOY15, "#str_07076"},
{"JOY16", K_JOY16, "#str_07077"},
{"JOY17", K_JOY17, "#str_07078"},
{"JOY18", K_JOY18, "#str_07079"},
{"JOY19", K_JOY19, "#str_07080"},
{"JOY20", K_JOY20, "#str_07081"},
{"JOY21", K_JOY21, "#str_07082"},
{"JOY22", K_JOY22, "#str_07083"},
{"JOY23", K_JOY23, "#str_07084"},
{"JOY24", K_JOY24, "#str_07085"},
{"JOY25", K_JOY25, "#str_07086"},
{"JOY26", K_JOY26, "#str_07087"},
{"JOY27", K_JOY27, "#str_07088"},
{"JOY28", K_JOY28, "#str_07089"},
{"JOY29", K_JOY29, "#str_07090"},
{"JOY30", K_JOY30, "#str_07091"},
{"JOY31", K_JOY31, "#str_07092"},
{"JOY32", K_JOY32, "#str_07093"},
{"AUX1", K_AUX1, "#str_07094"},
{"AUX2", K_AUX2, "#str_07095"},
{"AUX3", K_AUX3, "#str_07096"},
{"AUX4", K_AUX4, "#str_07097"},
{"AUX5", K_AUX5, "#str_07098"},
{"AUX6", K_AUX6, "#str_07099"},
{"AUX7", K_AUX7, "#str_07100"},
{"AUX8", K_AUX8, "#str_07101"},
{"AUX9", K_AUX9, "#str_07102"},
{"AUX10", K_AUX10, "#str_07103"},
{"AUX11", K_AUX11, "#str_07104"},
{"AUX12", K_AUX12, "#str_07105"},
{"AUX13", K_AUX13, "#str_07106"},
{"AUX14", K_AUX14, "#str_07107"},
{"AUX15", K_AUX15, "#str_07108"},
{"AUX16", K_AUX16, "#str_07109"},
{"KP_HOME", K_KP_HOME, "#str_07110"},
{"KP_UPARROW", K_KP_UPARROW, "#str_07111"},
{"KP_PGUP", K_KP_PGUP, "#str_07112"},
{"KP_LEFTARROW", K_KP_LEFTARROW, "#str_07113"},
{"KP_5", K_KP_5, "#str_07114"},
{"KP_RIGHTARROW", K_KP_RIGHTARROW, "#str_07115"},
{"KP_END", K_KP_END, "#str_07116"},
{"KP_DOWNARROW", K_KP_DOWNARROW, "#str_07117"},
{"KP_PGDN", K_KP_PGDN, "#str_07118"},
{"KP_ENTER", K_KP_ENTER, "#str_07119"},
{"KP_INS", K_KP_INS, "#str_07120"},
{"KP_DEL", K_KP_DEL, "#str_07121"},
{"KP_SLASH", K_KP_SLASH, "#str_07122"},
{"KP_MINUS", K_KP_MINUS, "#str_07123"},
{"KP_PLUS", K_KP_PLUS, "#str_07124"},
{"KP_NUMLOCK", K_KP_NUMLOCK, "#str_07125"},
{"KP_STAR", K_KP_STAR, "#str_07126"},
{"KP_EQUALS", K_KP_EQUALS, "#str_07127"},
{"PAUSE", K_PAUSE, "#str_07128"},
{"SEMICOLON", ';', "#str_07129"}, // because a raw semicolon separates commands
{"APOSTROPHE", '\'', "#str_07130"}
You would use the names in the first column.
However, upon further testing, the game isn't recognizing when I press the END button on my keyboard. So maybe there's something non-standard in the way those keys are implemented in the OS.
Binding say F10 to "exit" works.