Are you looking for an 'off brand' flash that will still communicate with your camera for TTL metering etc? Or do you want an 'auto' flash that meters for itself? Or do you want a purely manual flash?
When using an off-brand flash on your camera, one thing to be concerned about is the trigger voltage. You would need to know the capacity of your camera and the voltage of the flash. Most cameras are pretty good these days but I don't know about yours. Most new flashes are pretty low but who knows?
What is your budget and what are you looking to use it for?