You surely won't read this, but this is my best shot: as of today, there's an offer at AZ-delivery (they use to have offers like this every couple of months) that allows you to buy three 8266 for 7€ (2.40€ a piece), one for 3.79€. Sadly, the offer don't extend to the pack of five, that is 20€ (still, 4€ a piece!)

https://www.az-delivery.de/en/products/nodemcu-lua-lolin-v3-...

I know I sound like a salesman, but if you subscribe to their newsletter, you'll get that kind of offers all the time.