With a fin area of 130x121.6mm any fan with 105mm mount spacing (120mm fan) will fit. Of cours what fans will fit depends on your case CPU clearance is and RAM height.
If a 140mm fan will fit over your RAM may I suggest the TY-147 fan. It will idle at 600rpm, is PWM, has 105mm mount spacing and depending where you live can be very low priced... £5.82 here in UK.
ehume did extensive testing of fans on Megahalems using 65 fans in 112 different setups showing cooling and noise for each fan.
His 'go to' fan is the San Ace 9G1212H101(1). He also liked the CM Blade Master, Scythe Slipstream 1600, and the Japan Servo fans