Tailor lost her sleeves initially -- arms go in these (8)
I believe the answer is:
holsters
'arms go in these' is the definition.
(firearms might be carried in holsters)
'tailor lost her sleeves initially' is the wordplay.
'tailor' indicates an anagram (I've seen this in other clues).
'initially' says to take the initial letters.
The initial letter of 'sleeves' is 's'.
'lost'+'her'='losther'
'losther' with letters rearranged gives 'holster'.
'holster'+'s'='HOLSTERS'
(Other definitions for holsters that I've seen before include "Receptacles for hand--guns, pistols etc" , "Holders for handguns" , "Sheaths for handguns" , "Gun holders" , "Sheaths for guns" .)