function plusTen(prices) {
  for (var i = 0; i < prices.length; i++) {
    var price = prices[i].contents;
    var sep = false;
    if (price.match(",")) {
      sep = true;
      price = price.replace(",", "", "g");
    }
    price = Number(price) + 10;

    if (sep) {
      // 桁区切り
      p = "";
      for (var i2 = 0; i2 < String(price).length; i2++) {
        if (i2 > 0 && i2 % 3 == 0) p = "," + p;
        p = String(price).substr(String(price).length - i2 - 1, 1) + p;
      }
      price = p;
    }
    prices[i].contents = String(price);
  }
}

var myDocument = app.activeDocument;
if (myDocument.selection[0] instanceof TextFrame) {
  var tf = myDocument.selection[0];
  app.findGrepPreferences = NothingEnum.nothing;
  app.findGrepPreferences.findWhat = "([0-9][0-9,]*)(?=[円圓])"; // 小数点、全角、漢数字は考えない。後方肯定
  plusTen(tf.findGrep());
  app.findGrepPreferences.findWhat = "(?<=[￥¥])([0-9][0-9,]*)"; // 小数点、全角、漢数字は考えない。前方肯定
  plusTen(tf.findGrep());
} else {
  alert("対象テキストフレームを選択してください。");
}