Sparkletots mattress

I really feel you on this, it can be so stressful trying to find the right fit when the school uses a specific type of cot. I don't have a child in Sparkletots myself, but maybe try asking the school admin directly since they sometimes recommend where other parents have bought from. You can also check if Mothercare or even Shopee has covers that fit standard cot sizes, as those tend to have a wide range lah.