iPhone 5S A1533/A1530
iPad 2, iOS 7.1
According to this page https://www.apple.com/iphone/LTE/ , the iphone5s model for the Czech Republic (carriers = O2, T-Mobile, or Vodafone) is the model A1457.
According to this page http://en.wikipedia.org/wiki/List_of_LTE_networks#Europe , the Czech Republic's carriers:
O2: band 3 or 20
TMobile: band 3 or 20
Vodafone: band 8
And from Apple's LTE page, model A1457 supports LTE band 3,8,20, so A1457 should be the model someone would buy in the Czech Rep.
Model A1533 also supports band 3,8,20, but if you buy it in the USA, you must make sure it is unlocked, not just non-contract.
Some carriers sell non-contract phones but still may have a lock on it requiring you to be their customer for a period of time before they unlock your phone.
Some carriers sell iphone5s that are already unlocked out of the box.
You should ask if this phone can get service in the Czech Rep. $702.82 is a lot of money, and this phone can be delicate sometimes.
iPhone 5S A1533/A1530