Every character on Jiǎoluò Shūwū read as fa in any tone — 2 readings total across the four tones. Pick the tone you mean.
If you have the sound fa but not the character, here are the 2 characters read this way: 发 (fā, to send out, to develop, hair), 法 (fǎ, law, method, the Dharma). They split across 2 tones, so the tone is what separates them.