the iPhone SE came out last March, and rumour is that it won't be updated this year. Will it likely see a price drop this cycle? Is it best to hold off till March to buy one?
Only Apple knows the answer to this question.
While one may think that Apple could lower the price it could in fact go up: Depending on the country you are living prices have been increased in the past due to currency fluctuations.
IMO it's unlikely that we will see a price drop for the iPhone SE. For Apple it's a device with a really low profit margin compared to other products. It has most of the iPhone 6s' internal specs so Apple is in no hurry to upgrade it either.
I think if you need a new iPhone because your old one is broken, buy it now.