Mine Severní pól o pouhé sedm metry.
The main verb is "mine" 3sg. present tense form of minout "to miss."
The subject is 3sg. implicit "on" (supposedly about Cimrman).
The prepositon "o" here reports difference; in this meaning it takes the acc. case of the numeral sedm.
pouhé metry 'mere .... meters' are subordinated to the numeral; thus, it must be in the gen. pl (for 5+numerals)