I only have experience with the name brand (read, expensive) flashes when it comes to swivel head flashes but
here's one that might fill your needs.
If you decide you want to go used market, this may serve as a guide..
High Trigger Voltages can damage your camera so be mindful of what you are getting.
If you decide that swivel isn't that important to you, the AF360 is a nice little unit that will allow you to use your camera to full ability, including wireless flash.
Don't know what Dragging the shutter is so can't help much beyond that.