Q-Workshop makes custom dice (for a hefty fee of course).
That being said has anyone considered adding additional types of dice in an effort to simplify the number or dice rolled at once, and to provide for more "throttling" of options? In a system loaded with custom widgets this seems completely bananas, but I just thought I'd put a hair brained idea out there to see if anyone else was clearly as nut-crazy as me.
Consider it though...Having a d8 Peril die would allow for an extremely easy way of reducing the number of misfortune dice that creep into a potential pool -or- it could increase the deadly nature of a test's misfortune. Challenge dice wouldn't work in the cases I'm thinking of because the introduction of chaos stars and double challenges, etc simply make them too caustic. The increased faces on Peril die would allow for an additional Challenge symbol and an additional bane symbol. Normally you have a 33% chance for a blank face to come up on a Misfortune die, with a "Peril" die you would only have a 25% shot...it's worse but not cascadingly so. Carrying it further you've only got a 11%ish shot of both misfortune dice coming up blank if you were to roll 2 of them. So the increased die faces on a d8 act as something of a middle ground. Ultimately it allows you to throttle a Series of Misfortunate Events in such a way that you can make it worse or better on a player as the case may need...without underplaying your hand or crushing them too greatly.
Same goes for Fortune dice. Toss out a d8 Fate/Plot/Deus Ex Machina die. There is an obvious bloat of fortune dice that a single dice pool can contain...so what if you had a d8 Fortune die that could replace a couple of the d6'ers in the pool? You are still providing an increased situational or persistent bonus, but you aren't getting into the problem of 2 dice in place of 1 or 4 in place of 3...it just gets worse as you go up.
There are plenty of situational "hey let's talk it out" and "GM discression" talking points as written in the rules that work out just fine with the dice as supplied (DAS new acronym!). As in any system, there are spaces where the mechanics feel a smidge too clunky. Rather than taking the time to build a 100pg house-rule document explaining how and when I apply various effects it just might be easier to throw yet another die type at my players and come up with a simpler solution to those random problems.
Overlapping conditions could be simplified by combining misfortune dice into peril dice (if the total pile of dice starts creeping beyond 12 or 15 or if certain penalties really are compatible). You could also solve the Superior armor quality problem by attributing all or some of the defence points for a suit of armor as Peril dice instead of misfortune. Poof the item is better and you don't have to keep straight all the myriad social situations that the 10x cost item benefits a person in, or which actions can be done when, or worry about the leather armor being better than full plate.
Before ever going so far as ordering 50usd of custom dice I think I might grab some d8's from my archives and tape them up with new symbols. OH and I totally realise I am insane and way overthinking a game that is intended to support group discussion and gm fiat. I just see a potential blind spot in the rules that could be shored up easier with more crud to lug around.