[villagetinker]

Never tried good feet store, but I found the "arch fit" sneakers to be very helpful, I even found suitable inserts for bowling shoes. I went through the custom made HARD orthotics and found my knees were hurting during the week (I was working, office attire was leather shoes) and knees were fine on the weekend as I was wearing sneakers with SOFT inserts.
IMHO (I have NO medical experience) I would try the arch fit sneakers or at a minimum RUNNING sneakers as both of these have additional support, then a suitable exercise or rehab. When I was in rehab for a shoulder injury, I saw other patients going through exercises for balance.
Last thing, I have balance issues due to an inner ear problem and i know there are certain things I must avoid, you may want to have a suitable doctor check this out also.