Princess Cadance and Shining Armor are sadly just Target exclusives as I've mentioned, and they are no longer available on Target's website. However you can use this page , the item page, to see if your store possibly has them. These are not always 100% correct, but they are usually correct far as Target for me.
These ponies are absolutely beautiful, being the fashion ponies which are much bigger compared to the usual 5 dollar ponies. Fashion ponies typically cost 15 dollars a piece, and the mane 6 and princesses have all gotten ponies for the set. These two come with several small accessories as all fashion ponies do so you can put barrettes in their hair etc. They always come with clothing the girls typically have a cape like dress with Shining armor having the first actual shirt that I've seen on a fashion pony, though I haven't gotten all of the fashion ponies yet.
I find the fact that shining armor has been giving a mohawk rather amusing really, I see no reason for them to have done that. After all his hair was nothing like that in the series, however they may have been wanting to distinguish him as a male pony. Beyond that though I rather like these two ponies, they are very beautiful and the fashion ponies are just fun ones to get even if they are more expensive then most of the ponies.
If you are hoping to get these but don't have a target in your area there may be another solution to it. A while back Target also had a Princess Luna and Celestia two fashion pony pack, beautiful set and came with a lot of accessories. However now they have these two ponies as individual ponies available everywhere, the only difference being in some of the accessories and the lack of tinsel in the newer editions. They may end up doing the same for these ponies, but if you see them in a store I do highly recommend getting them now just incase they don't come out. The prices are already going up because of it being a Target exclusive, as all exclusives tend to get expensive.
I highly recommend getting these ponies for your pony fan's collection, they are great to play with and just to have to display in a collection.