mountaineering boots for high arches

A friend of mine is looking to join my group for for a trip to Mt Rainier next year. And she has super high arches in her feet.  I told her I would help do some research for what would work best for her. Do any of yall have any experience with this issue? Is a there a boot in particular that would work best or are insoles going to be the best route for her? We're also located in the south east, so going to our local REI or outdoor store to try on boots is kinda out of the question since we don't really have mountains here.  Any advice is greatly appreciated.  

You may want to consider different insoles rather than specific boots. Superfeet Greens seem pretty popular for folks with higher arches. 

REI would probably order the boots for her to try on in store.

Insoles I like Tread Labs. Their "extra high" model is higher arched than anything I've gotten from Superfeet. 

Awesome thanks for the info! I was unsure of how to help her out on this issue.

I have high arches and tend to like la Sportiva. superfeet green are great for high arches. I have had many pairs. Currently I have sportivas and super feet mint.

take a side trip to a place like  Neptune Mountaineering in Boulder and buy boots there. 

Footwear manufacturers do not make boots / shoes with any kind of meaningful arch support for people with high arches.  Inserts are going to be needed.  What does she use in her other footwear?

I have Sportiva nepal cube's.  I tried the superfeet redhot insoles in them which provided zero arc support.  Based on the amount of money wasted on those I have not tried any other superfeet insoles.

I have been using these ProFoot arch supports in all my footwear for years.  These are the only thing I have found that provide any support what so ever for my feet.  Found them at Walmart then Walmart stopped carrying them.  I have even modified a couple pair by cutting the gel heel pad out.  Not cuting a hole all the way through, just removing the jell to make a deeper heal cup.  I have also built up the bottom of the arch area with climbing tape on the ones in my climbing boots.  Full discloser, I also have Sesamoiditis in my left foot that I am dealing with.

I have high arches, high insteps, semi-wide feet; super feet green or their winter insole works fine for me and I use boots built around higher volume lasts.