Hi Cal, and welcome to the hobby and to the forum!
As others have said, the 14" aluminum horns aren't particularly rare, but they usually command a high price. In our hobby, rarity doesn't always equate to value, as in the case with "off-brand" phonograph brands from the teens and early 20s. Likewise, certain relatively common items usually bring strong prices, such as the Victor VI, Edison Opera, the Berliner Improved Gramophone, and aluminum Columbia horns. Your horn is worth more than what you paid for everything. Congratulations!
If you haven't already discovered it, the Antique Phonograph Society has a website with a number of interesting articles in various categories: Introductory, Intermediate, Advanced, Technical Series, and even a Book Feature. You can freely access all the articles and other things at the APS Home Page:
http://www.antiquephono.org/
If you look inside the lid of your Q, you may see a paper label marked "QA." That was the original designation for the Q when sold with an aluminum horn. Original price was $10.70.
George P.