One of the major stores in the Washington DC area used to carry Diezels. I tried a VH4 there in late 2008, during the recession. The price was to high for me at the time, and I got a 20% off coupon good for ENGL at an online retailer, so I ended up buying the ENGL Invader instead, which I had also demoed at the store. I gave them the chance to match the online price, but the sales guy said he couldn't do it, so I bought online from the more desperate dealer.
Fast forward to late 2017, and the store had entirely stopped carrying Diezels, and were trying to get rid of their last big ENGLs by heavily discounting them. The sales guy I talked to that time said they couldn't move the big expensive amps, and the distributor wanted minimum orders of something like $25,000 or more, and they just couldn't justify it. Meanwhile, they sold several Hughes and Kettner tubemeisters that week, because they're portable, fairly cheap, and have some pretty lights and convenient features.
In between, maybe 2014 or so, I found a used VH4 on ebay for $3,000, so I bought it. I still have both amps.
Since then, I have noticed the price of Diezels has actually gone down a bit since 2008, both new and used, and where several years ago only one or two would show up now and then on ebay, when I checked maybe a year ago, there were several listings at a time.
What's happening is a mix of three things. First, people are moving from big gear to small gear. Second is the longstanding move to shopping online, which makes it much harder for physical stores to justify carrying big, expensive gear on site. Finally, as a result of new tech developments going beyond just the basic internet thing, as in bandwidth that allows for streaming video, huge advances in software, and basically ad hoc manufacturing, the market is currently flooded with gear, with new brands popping up every year and YouTubers who may never have built anything in their life now with their own lines of guitars courtesy of factories in Asia, or "custom" pedals made by taking an existing circuit design with maybe one or two minor changes to the feature set and putting it in a slightly different case with a different paint job.
The ironic result of all of that is there is more gear than ever on the market, but very little of it is available to try in person. The physical stores will only carry what they're confident will sell. On the plus side, some online stores will give you 30 days to try, and then you can send it back, but usually you'll have to pay return shipping and often a restocking fee due to the fact that they can no longer sell it as new. But while that can get expensive, it's better than not having any options at all.
So your options are probably buy to try, or find someone on Craigslist or a similar site who's selling theirs, or take a short vacation to somewhere that does have Diezels.
