Hello.
This is my first time posting since the forum website was totally revamped (yet again). (Have to say I'm not fond of the new version/site at all).
Anyway, if the original submitter of this thread is still following it, here's my reply:
Sometimes the year of manufacture was incorporated into the serial number and/or the year of the model's debut incorporated into the model number, but not for the earlier Ridgeways with three-digit model numbers. By the time they moved to the four-digit model numbers the year could be determined much more easily. For the three-digit model numbers, you kind of have to rely on old catalogs, of which I have a few (ca. 1967, ca. 1972, 1977, and 1997).
Model 112, also known as "The Wakefield," appeared in the 1972 and 1977 catalogs (but not the 1967 catalog, even though there were already model numbers sequentially higher than 112 by that point...go figure). In 1977 its suggested retail price ranged from $999 to $1399, depending on which type of movement was included. (But as for current value, keep in mind that new clocks are like new cars--their value greatly decreases the moment they leave the showroom floor, and it takes many years for them to re-climb in value. Some never make it back).
If I can figure out how to attach images to this post via this new-fangled forum, I'll attach a couple of images from the 1977 catalog.
Enjoy your clock!

John