I checked NAPA and Kragen online.
NAPA part # is:
NF LF12K - $11.99 - flasher/turn signal (loud flasher kit)
NF LF12 - $10.99 - flasher/turn signal (loud flasher)
NF EL12 - $10.99 - flasher/turn signal (electromechanical flasher)
They are all made by Tridon and are all the better heavy duty electronic (electromechanical) flashers, not the standard duty old (thermal) style.
Kragen also has some of the same, plus a couple others online.
http://www.partsamerica.com/SelectP...hfor=Flashers&destinationpage=SelectParts.asp you'll have to input your zip code and then year, make, and model of vehicle - then the page will come up.
They have the standard duty flashers as well as the EL12 and LF12 listed above. The EL12 is the same price, the LF12 is $8.88, so a little over $2 cheaper. The standard flashers are from $2.99 to $3.59 for the proper units depending on whose name is on the package it comes in. Tridon number is 552, Borg Warner is FC552 (most likely both made by Tridon anyway).
Check elsewhere online for more.