Help ID/dating/fixing?

After Super's help dating our C12, I took another look at this train...
It's broken in a very bad place, without the shell on to hold it together it literally falls apart.
It has no date and even less of a logo or markings as the C12.
Any ideas how old this one is?

[Super]

Thats a tough one. It looks to be a D-51 possibly from the first early releases of a steam engine which came without a tender. I can't locate one that has that red Tomy sticker or any of the vintage series with Tomy on it. This leaves me to believe this came in a set with track and accessories although thats just a guess by me. Can you match up what the metal motor looks like with the chart posted in the other thread? That may give an idea of around the year it was released. Is the metal housing completely covered on top? This one also has the solid side rods which seems it would indicate its a tad older that your C-12. The Tomy Logo on the bottom of the chassis should give at least a starting point as that Logo first came to be in 1967 and used until 1981.