Weapons from revolutionary times, externally unchanged (8)
I believe the answer is:
assegais
'weapons' is the definition.
(assegai is a kind of weapon)
'revolutionary times externally unchanged' is the wordplay.
'revolutionary' says the letters should be written in reverse.
'times' becomes 'ages' (age is a kind of time).
'externally' indicates putting letters inside.
'unchanged' becomes 'asis' (I've seen this before).
'ages' back-to-front is 'sega'.
'sega' inserted within 'asis' is 'ASSEGAIS'.
'from' is the link.
(Another definition for assegais that I've seen is " Zulu Spears".)