First off, I'm not applying for the 501st, and I'd rather my costume be comfortable than accurate (which is why I believe I'll always use a modified t-shirt instead of flak vest, and usually leave off the hoses on the gaunts). With that in mind, I've got some ideas to share on guantlet darts...
My first set of gauntlets (the first thing I worked on for my Fett after buying an awful Rubies bucket) had 3 screw on spikes in place of the darts. I took these off of my high-school backpack which had been used storing spray paint cans for the last 12 years. Ah, to be punk in the late 90's... Anyway, these look neat, but are nowhere close to accurate. They're be great on a Mandalorian. I don't recall where I got em in 1998, but you can probably still buy them from a website like Hot Topic. I should probably use these for toe spikes, although I've been putting off adding toe spikes cuz I feel they might intrude on the comfort of wearing the costume because I'd constantly have to be aware of em to not stab anything accidentally.
I'm rebuilding the gauntlets now (you can see why in the pics: inexperienced builder with plaster on cardboard and forsale signs is not a good look), using purchased vac-formed tops and sintra clamshells and I'm thinking about what to use for darts this time around. It happens that I'm still punk enough to have some bad instrument cables lying around and I'm thinking about just cutting the 1/4" jacks off of 3 or 4 of those. They're about double the width of the accurate darts, but the shape is right. What do you guys think?
P.S. That's a Lobot headset in the background that I'm hoping to finish for my bald friend before Dragon*Con