Plarail 3-way Automatic Point Rail

I excavated the ones I have, which are the middle Plarail R-16 and the Tomy Train versions. As expected the only significant difference is in the shape of the actuator. Also note that this particular Plarail one has "TOMY" moulded onto the upper surface beside the fence (which is different from the otherwise identical version shown in the photo in my first post with 16 written on it).  I'd be interested to know what other dates anyone else might find on the reverse of theirs.