TheResearchChemsLab (verified vendors section) has some in what I assume is powdered form.
Your doctor will not help you with your benzo taper, at least not on your terms. Addiction treatment in the US sucks. You'd be better off doing it yourself.
I was a long-half-life benzo addict for the better part of a decade, starting from when I discovered I could order drugs online when I was 17. I started with phenazepam, clonazepam, and etizolam. Eventually, when clonazolam and flubromazolam hit the mark I was literally over the moon. And shit, I finished my nuclear engineering degree and my subsequent photonics masters while doing 2-4mg of flubro a day; I learned quickly though that clonazolam removed all of my inhibitions and made me do shit I regretted, so I stopped with that shit.
Enjoyed flualprazolam when it came out. Best body load from a benzo ever? I still think maybe so. However, it makes me buy shit like a crazy person. I took a flualp to sleep a few months ago, and instead of sleeping, I built and purchased an entire deck of Yu-Gi-Oh cards to take to the local tournament. I have a renewed interest in an old hobby thanks to flualp, and it wasn't a lot of money, but BE CAREFUL. When I'm under the influence of flualp specifically, I'm very vulnerable to micro transactions in video games as well.
Anyway, tapering off with avizafone is literally textbook Ashton manual, with the added bonus that if you pour some avizafone solution into an empty epi-pen, you'll be prepared if you're ever attacked with nerve gas (I shit you not, that's what avizafone is actually for). I tapered off nasty benzo dependence twice using diclazepam, with no input from any doctor. I had zero issues and only about a week of insomnia after the final taper, which I would resolve on every third day with a z-drug if it didn't resolve on its own. I stopped needing the zolp before I ran out.
I have some of Autogen's solution. The first time I took it, my expectations were low because subconsciously I had always considered Valium to be the boring one that everyone went and improved on. Man, could I have been more wrong. I did 30mg (not unreasonable given my experience with benzos) in preparation for bed, hopped in the shower, and ended up giggling uncontrollably to myself in the mirror for like half an hour. It was fantastic; I felt like a wiggly jello person and had amazing muscle relaxation. I fell asleep after some video games (in which I did NOT buy any MTX).
The problem is (or in your case, the upside) that it's so damn long. I've never had Valium before and was not expecting it to carry over to the next day so much. Even fucking phenazepam you could kinda sleep it off. No delusions of sobriety, though, I looked at myself in the mirror and said "god damn it, I'm still barred out."
So, make yourself a spreadsheet calendar in Microsoft excel. For long benzos you can start with two doses a day. First few days reduce to 90% your current dose just to establish the habit; you might even feel some discomfort even at that level, use that to get into routine. Reduce your morning dose before your night dose by a few days at least (better to be on edge, but awake, rather than unable to sleep).
Iirc, I shot for a 5 week taper, which is pretty short, but then I left room for a few weeks of minimal maintenance dosage if the short taper really fucked me up. It didn't and I ended up tossing my benzos about a week after my final dose.
Now I'm back here on the drug forum, and I certainly buy benzos. I only buy the short and medium duration ones, and really only enough to keep around as a safety measure when doing other drugs, and possibly to sleep if I'm just insomniaing so hard the night before something important, I made my peace with those drugs, and honestly can't understand why I found it enjoyable to do everything benzed. I still like smoking weed and doing shit, but benzos are for nap time.