Any decent shoe repair facility should be able to double/treble a shoe heel and sole.
To be honest I would get some custom shoes made with the lift installed inside the shoe.
Having said that, what it cost to have my shoes repaired last time, it may be cheaper to have the other hip done , and set to the correct length!
THE BEST 10 Shoe Repair in The Villages, FL - Last Updated December 2021 - Yelp