The 717 is, as of this 2011 writing, the central pillar of Dollar’s fountain pen output. I say this not because it is a particularly grand pen, but because it comes in more variants than Dollar’s other models. The base model 717i, if one may speak of it that way, is a fairly undistinguished screw-cap, piston-filling pen, with a small ink window near the section (in common with almost every other piston-filler in the world). The 717iT is broadly known as the Dollar Demonstrator for its clear body; the T stands for transparent.
These two variations have red, blue and grey/black components (I have a vague memory of green being available as well– if you can confirm this, let me know), but all come only with a fine point. This is a contrast with the European makers, which seem to think medium points are most appropriate for student pens. I honour Dollar for this, as I think kids have enough trouble not closing the letter e without having a wide point forced on them. I know I did.
The last variant is in the catalogue under two different names: 717q and 717c. The letter stands for “qalam” or “calligraphy”, respectively, and it differs from the 717i in that the point is shaped specifically for calligraphy. While it claims to be specific to the calligraphy in the part of the world it’s from, it is in fact simply an italic point with a slightly oblique end.
My only complaint about this pen is a minor one– with a short and relatively uncomplicated feed, it is subject to dribbling due to thermal expansion when the ink starts to get low. If used in what to this Canadian would be an oppressively warm setting, this problem would hardly appear. There is also no inner cap and no venting to the cap, so the feed might flood if the pen is opened with the point down, a small issue easily addressed by opening it with the point up.
Production Run: 1954 to present (I sent an inquiry to the company seeking more detail about their history, and while the response was terse I was given the word that the 717 was in design before Dollar was actually established).
Cost When New: 15 to 20 Pakistan Rupee (exported to Europe and North America, it can be found on the internet for $10 to $15, which is still a fair price).
Size: 12.6 cm long capped, 14.6 cm posted, 11.6 cm uncapped.
Body: Polystyrene, I should think.
Filler: Piston, capacity approx. 1.4 ml (this is surprisingly large, given the pen’s overall dimensions).
If you are relying on the preceding information to win a bet or impress a teacher, you should read the site’s scholarly caveat. Remember, this is the internet, and it’s full of bad information.