Still not convinced about 30a It can 21 stock (4) S?E?
(21 being SCAN)
SMEE - pirate link but how does it connect with 'scan'?
SPET - don't know that acronym can find no relevance to clue
STEM is what I had - ties in with stock in Chambers but not with scan. Don't think it's correct either!
Any more brainwaves?