That sounds like a very reasonable price for 1000 crix. If found that the insects need more care that the leos, so here is some of my advice about the care of crix.
Temperature is a very key element when keeping a large number of crix. Each cricket container should have some sort of heat source applied to it. I use a 30 watt bulb hung just below the lip of the container to heat my crix. Another critical factor is ventilation; they need lots of fresh air, and make sure to take out any dead crix when you see them.
I use a plastic dish with vermiculite for the adult crix to lay eggs in, it should be misted daily. Every time I’ve covered the dish, I’ve had trouble with mold, so I leave the lid off, and try to keep the eggs warm (80-95) deg.
Make sure to provide a good gutload (dry food), I use Fluker’s cricket feed because it is readily available, and the crix seem to love it. There are plenty of other good gutload mixtures out there. They should also have a fresh moist food like potato/carrot/apple to provide them moisture.
You can expect crix to live 8-10 weeks. I think the most nutritious crix are between ½ and ¾ inch. Right before they grow wings is the ideal time to feed them off to your geckos.
I don’t use a substrate for crix, but it may work for you. Just make sure to toughly clean the plastic tub between batches of crix. I hope this helps, and please let me or the forum know if you have any more questions.
DaveCable