Does ख़ really sound different here than ख? It should sound like a fricative consonant but for me they both sound the same.
According to my wife who is a native speaker, ख़ is commonly pronounced as ख in Hindi. The fricative sound is mainly used in Urdu.
Can it also mean a letter of the alphabet or is it only a postal letter?
Some googling tells me there was a brief instance of Wheel of Fortune in India in the 90s tho I couldn't find any info about it. Was it in English? Were the most common letters RSTLNE? How could a Hindi Wheel of Fortune be designed? Fun stuff.