如何在elementui select组件基础上实现“加载更多”

<script src="//unpkg.com/vue/dist/vue.js"></script>
<script src="//unpkg.com/element-ui@2.13.0/lib/index.js"></script>
<div id="app">
<template>
  <el-select v-model="value" placeholder="请选择">
    <el-option
      v-for="item in options"
      :key="item.value"
      :label="item.label"
      :value="item.value">
    </el-option>
    <el-option label='加载更多' value="undefined" @click.native='handleClick($event)'></el-option>
  </el-select>
</template>
</div>

// javascript
var Main = {
    data() {
      return {
        options: [{
          value: '选项1',
          label: '黄金糕'
        }, {
          value: '选项2',
          label: '双皮奶'
        }, {
          value: '选项3',
          label: '蚵仔煎'
        }, {
          value: '选项4',
          label: '龙须面'
        }, {
          value: '选项5',
          label: '北京烤鸭'
        }],
        value: ''
      }
    },
    methods: {
      handleClick(event) {
        this.value = undefined,
          setTimeout(() => {
            this.options.push(...[{value: '选项6',
          label: '武汉鸭脖'},{value: '选项7',
          label: '广式早点'},{value: '选项8',
          label: '云南普洱'}])  
        }, 1000)
      }
    }
  }
var Ctor = Vue.extend(Main)
new Ctor().$mount('#app')

如上所示，实现了“加载更多”功能的代码，可以考虑在此基础上对element select进行封装。