Check if this can be useful for you. I have modified the JS file a bit, download the attached plugin.min.js file. Change the width and height values ( Line no #31, 32 )as per your need.
tinymce.PluginManager.add("emoticons", function(a, b) {
function c() {
var a;
return a = '<table role="list" class="mce-grid" style="padding: 10px">', tinymce.each(d, function(c) {
a += "<tr>", tinymce.each(c, function(c) {
var d = b + "/img/smiley-" + c + ".gif";
a += '<td><a href="#" data-mce-url="' + d + '" data-mce-alt="' + c + '" tabindex="-1" role="option" aria-label="' + c + '"><img src="' + d + '" style="width: 18px; height: 18px" role="presentation" /></a></td>'
}), a += "</tr>"
}), a += "</table>"
}
var d = [
["cool", "cry", "embarassed", "foot-in-mouth", "frown", "innocent", "kiss", "laughing", "money-mouth", "sealed", "smile", "surprised"],
["cool", "cry", "embarassed", "foot-in-mouth", "frown", "innocent", "kiss", "laughing", "money-mouth", "sealed", "smile", "surprised"],
["cool", "cry", "embarassed", "foot-in-mouth", "frown", "innocent", "kiss", "laughing", "money-mouth", "sealed", "smile", "surprised"],
["cool", "cry", "embarassed", "foot-in-mouth", "frown", "innocent", "kiss", "laughing", "money-mouth", "sealed", "smile", "surprised"],
["cool", "cry", "embarassed", "foot-in-mouth", "frown", "innocent", "kiss", "laughing", "money-mouth", "sealed", "smile", "surprised"],
["cool", "cry", "embarassed", "foot-in-mouth", "frown", "innocent", "kiss", "laughing", "money-mouth", "sealed", "smile", "surprised"],
["cool", "cry", "embarassed", "foot-in-mouth", "frown", "innocent", "kiss", "laughing", "money-mouth", "sealed", "smile", "surprised"],
["cool", "cry", "embarassed", "foot-in-mouth", "frown", "innocent", "kiss", "laughing", "money-mouth", "sealed", "smile", "surprised"],
["cool", "cry", "embarassed", "foot-in-mouth", "frown", "innocent", "kiss", "laughing", "money-mouth", "sealed", "smile", "surprised"],
["cool", "cry", "embarassed", "foot-in-mouth", "frown", "innocent", "kiss", "laughing", "money-mouth", "sealed", "smile", "surprised"],
["cool", "cry", "embarassed", "foot-in-mouth", "frown", "innocent", "kiss", "laughing", "money-mouth", "sealed", "smile", "surprised"],
["cool", "cry", "embarassed", "foot-in-mouth", "frown", "innocent", "kiss", "laughing", "money-mouth", "sealed", "smile", "surprised"],
["cool", "cry", "embarassed", "foot-in-mouth", "frown", "innocent", "kiss", "laughing", "money-mouth", "sealed", "smile", "surprised"],
["cool", "cry", "embarassed", "foot-in-mouth", "frown", "innocent", "kiss", "laughing", "money-mouth", "sealed", "smile", "surprised"],
];
a.addCommand('show_emoticons', function() {
a.windowManager.open({
title: "Emoticons",
width : 300,
height : 200,
html: c(),
onclick: function(b) {
var c = a.dom.getParent(b.target, "a");
c && (a.insertContent('<img src="' + c.getAttribute("data-mce-url") + '" alt="' + c.getAttribute("data-mce-alt") + '" />'), this.hide())
return false;
},
inline : true,
autoScroll: true,
scrollbars:true,
buttons:[],
}, {
plugin_url : b // Plugin absolute URL
});
});
a.addButton('emoticons', {
title : 'Emoticons',
cmd : 'show_emoticons',
});
});