jQuery placeholders substitution
[$[SKU001]$]
[$[SKU002]$]

<img src="SKU001.jpg">
<img src="SKU002.jpg">

var pattern = /[$[(.*?)]$]/;
var t = $('body').filter(function() {
    return this.??.match(pattern);
});

console.log(t);

var matches = $('body').text().match(/[$[(.*?)]$]/)
console.log(matches);