I would try some searches for Shrimp groups online and in places like Facebook (with facebook or even Gumtree or Craigs list you might find people already local to you with shrimp available), often if you can get in contact with a breeder direct not only will you get a better deal but also you can talk to them directly about the water parameters they are keeping and breeding their shrimp in. It truly is amazing just how much the pH and gH of the water can influence the colouration of the shrimp as well as what foods they are getting.
I have seen shrimp that where amazing knock out colours reduce their wow factor when put into a different tank with different setup and parameters and visa versa can also happen, where plain Jane shrimp turn stunning when put into condtions that are more suitable to them.
The other bonus of getting some "cull" shrimp from a breeder is if you have the time and interest you can try to develop your own line of shrimp.
And no matter how tempting it is (trust me the temptation is great) don't mix different colour variations of cherry shrimp in the one tank, yes the adults will look amazing being a mix of red, yellow, orange, rili, blue green and black....BUT the jumbled mixed genetics of the offspring that such a blending will produce will only look like wild type cherry shrimp which no body wants and generally become fish food.