[rayjay]

Sorry, but from what I read in your post, I believe it best by far that you DON'T buy the seahorses at this time. Maybe buy some something manufactured that pictures or is in the form of seahorses along with an I.O.U..
It will take you some time to research what you need to know and to buy for your setup and to do it before Christmas is most likely to lead to failure and deaths.
I was reefing for about 10 yrs before I added seahorse tanks, and then found out that the reefing experience was not all I needed for success.
Even now, fourteen years later, I'm STILL learning as the hobby has evolved SO much over that time span.