[Nexus]

Может как-то так?

const ids = [132, 133];
const minQuantity = 5;

[].forEach.call(document.querySelectorAll(ids.map(id => `#quantity${id}`).join(', ')), node => {
    node.addEventListener('input', e => {
        const id = node.id.replace(/\D+?/g, '');
        document.getElementById(`productlink${id}`).disabled = +node.value.trim() < minQuantity;
    });
});