Hey,
I can understand your concerns. I may not be able to help you directly but hate reading and running!
I too wanted to purchase recently two healthy gecko's and did everything i can only to find i have concerns about one of the two's motions within a couple of days! (Of which i'm hoping my concerns will be resolved at the vets shortly)
Perhaps by from a reputable breeder rather then a reptile store.
Unfortunately i'm unsure as to any close to you! It may involve a ride out but i'm more then sure it would be worth it for peace of mind!
All the best,
Casp.