NRF51/52 analogues. DIY Keyboard. What to buy?

Question

Do it yourself

You need a microcontroller for a keyboard with a wireless connection. What options are there besides NRF51/52. Prices for NRF51/52 on ali crane are great.

Answer 1

Not advertising for the sake of it, just as an example - cheap enough ? :D
And in the end, what prevents you from buying not a "supermodern" version, but one that was perfectly used a week ago for the past two years for the same thing? -> NRF24

Answer 2

There, the final price is 700 rubles, just the main amount is laid down like in "delivery". The Chinese are such "marketers" ...