I have one of the Larbel's like the one Yoda converted, pictured at the start of the thread. It came with a Parks blade (I wouldn't know what distinguishes the Parks internals, mind) and came with a stand that has a couple of LEDs in the base to light the vinyl and a plaque with "Star Wars/Episode I: The Phantom Menace/Obi-Wan Kenobi/-Larbel EL Lightsaber-/Limited Edition: 1999/2500".
I did think it may be a Parks when I first got it on account of what I'd read about the Larbel's having the deeper grip grooves.
I'm guessing that it's down to variations in different runs from Larbel, but not 100% on that. I did see a pic of an Parks EL Obi Wan from Vortextwist on the forums here that had some differences to my Obi-Wan in the emitter area.
I also owned a stunt version from Sithplanet before this which had the deeper grooves and was 3/4" hollow from emitter to pommel, with the inner area of the emitter around the blade-hole recessed. I've also heard that some of the stuff Sithplanet has sold is Parks, which doesn't help.
I think you're right about Lightech - they have a nice line in Blade Runner-style lit umbrellas though!
The bottom line is, I'm just happy to have a very nice lightsaber :D