I wrote around 3 1/2 pages for mine I think so between 550-600 words. It’s less about the word count and more about your use of Irish, while obviously don’t write half a page and hope that that’s enough, don’t stress too much about the length.
I think the best thing to do is make sure that your grammar is as perfect as you can get it. I learnt off 1/3-1/2 page long sections on most of the topics Sod it mentioned and also a number of useful linking phrases. Then I just threaded together what I could to suit the essay title I chose.
Learning off an essay can either work brilliantly or end terribly depending on the titles…one guy in my year flew through his essay in 25 minutes, one girl started crying the second she looked at the titles as none of her essays fitted them…!