Stagg's BJH-B20D blues harmonica is a great little instrument that will not let you down.
Despite its name, this harmonica is very versatile and can be used in many different genres of music such as folk and soul, as well as blues.
N.B. It is worth bearing in mind that when using a harmonica for blues playing, it is generally preferable to use a harmonica tuned to the 4th note of the key in which you are playing. With this in mind, this instrument would suit blues music played in A major, as well as F# minor, B minor and D major.