I was not sure if anyone would be interested, but found the following lights on Ebay. They arent exactly period, but could make for a decent replacement light. I have not ordered from this vendor before so I cant state these to be a quality product.
Mike, I asked Mark [Pink MG] about ADDING LEDs to the rear of my TD in addition to the existing lights. He said that the two types would work together with the regular flasher when wired into the same circuit. However , if you REPLACED the front lights with LEDs, I wonder if the effect might be a faster blink like can occur when a bulb has burned out. Not sure about this ,just reasoning that a flasher designed to blink properly with two bulbs,would not work the same if half of the load was removed and replaced with the smaller draw of the LED.