Hatching eggs you get almost only at the internet , if you do not know any holder / breeder personal.
When selecting the source the price should not play the decisive role , but rather the impression you get from the breeding facility (not always easily on the internet , but each breeder who is proud of his animals has pictures, which he likes to show) . In the end it does not matter if you buy 12 eggs for 2 € or 5 €, if the fertilization rate is higher or the genetic material is better, the money is well spent.
Another selection criterion may be what colour the quials has. You get easyer and cheaper colormixed eggs. I also have just mixed hatching eggs in supply.
As hatching eggs you should only use very clean eggs, with a normal weight and normal -shaped eggs.All other eggs belong in the kitchen, not in a breeder.