Looking for Focal Stella amplifier suggestions

My main headphone listening setup uses a 10.5” iPad Pro, running the Onkyo HF app with lossless and often hi-bit files into the Apple USB/Lightning adaptor. From there a Dragonfly Red is run with some old Monster brand ⅛” to RCA jacks and into the Massdrop Alex Cavelli tube hybrid amp (CTH). I am using the Stellias with the Focal 4-pin XLR jacks. 
Prior to the Stellias my main phones were the Shure 846’s. I listened to those for many years prior to the Cavelli purchase and thus was truly blown away by the difference the Cavelli made to the entire soundstage and dynamic range. So, I know that I do like the Cavelli and appreciate the difference it makes to the Shures. 
Having never tried any other amp with the Stellias, and enjoying the Stellias but also finding them to have a very closed soundstage I’d be interested in trying a different amp. Might have considered the Arche but not thrilled that it was discontinued. I’d would love to hear any feedback for choices (particularly if they could be home-tested and returned if necessary). My small town does not have any hi end audio shops anymore and other than Best Buy no other audio options. Thanks for your time!
Stellas fortunately are pretty easy to drive. They will benefit from upgrades of all your equipment for a long time to come. I prefer the natural tube sound and use Woo headphone amplifiers. I can recommend the WA6, WA6se, and definitely the WA5... which is an order of magnitude better than the other two. The headphones will also greatly benefit in upgrading to a high quality streamer and DAC. I am fortunate to have high quality Aurender streamer and Ayre DAC. Each costing many thousands... all the steps getting their are well worth it and complement these excellent headphones
Quicksilver Headphone Amp, but you’d have to work with a dealer (or the company) to see about a home trial.  Best of luck. 

I have a chance to purchase a demo pair of Focal Stella for 64K Dealer says they re 1 year old in mint condition.  I am not able to see or hear them in person. Anyone think this is a good price?  I could really use some advice, thanks

I run Focal Elears. In an A - B shoot out between these and the electrostatic (or something like that tech) Hi-Fi Man HE 400i, the victor was clear. Being conscious of volume adjusting prior to evaluations, the Focal was MUCH better in everyway. (I was the owner of the HI-Fi Man set so I was biased in favor of my "dog" in this fight.) Our headphone amp was the older tube Cayin HA-1A without speaker outs. We felt like we'd gone from a 70's pair of Koss to the modern age of musical magic. The one word that came to mind was "gravitas". The Focals presented a world class environment when powered by the Cayin, Therefore try and audition the Cayin with Focal's, I'm pretty sure you'll be amazed as we were. (Direct feed from rear of Nuprime DAC 9SE from Audiolab 6000CDT transport)