the Omega Juicer is reputed to be one of the best juicers on the market, so you have made a good choice there.
Many juicers tend to be of the "centrifugal" type, and I think it is a fallacy that they generate heat to destroy the enzymes or any other living part of the fruit/vegetable.
The most efficient juice extractors though, in terms of quantity and quality are the "press- type" juicers, such as the Norwalk Juicer recommended by The Gerson Anti-Cancer protocol, but they are very expensive!!!
I personally use the Jack LaLanne juice extractor, which I find to be extremely good and not that expensive.
I would personally try to get some help with the shopping and so on, if possible, to take the strain away from that responsibility or indeed having the energy to do so in the first place.
Sheltons view on stones (kidney, gallbladder, Liver or wherever) is that they are formed by a faulty metabolism created by an unnatural and denatured diet; this tends towards the precipitation of abnormal secretions and excretions, resulting in stone formation. When metabolism is normalized thru the correct diet, with a preliminary fast, they are dissolved by normalized metabolic secretions and excretions.
Juicing followed by a a mostly raw diet would be a good idea in achieving these aims.