I found a reading suggestion as I was learning this suggestion that I thought might help. The existing explanation talks about being stuck in a scary dark cooler
Sure, くら does sound a little like cooler, but what I found helped remember the word itself was thinking:
You’re trapped in a dark room. Was that a noise? You can’t see, because it’s so dark. In fact, it’s so scary and dark that you start to cry (くらい)
I feel like more people can probably relate to that mnemonic from childhood memories of fear of the dark. Granted, I realise that reading explanation is to help with the kanji reading, but you’ve used examples for whole word sound in other vocab like cashew for 歌手.