seemer = "someone that gives the impression of being something or having a particular quality but who isn't genuine; a dissembler" = person making a show.
Nikki, thanks for 'howlet'
. I haven't settled 'seemer' yet - I'm still puzzling over 16 A.
Thatcher's mentioned wallets for prisoners (7)
r?eders.
I can see 'reeders', which fits the 'thatcher' bit, but I have no idea re 'wallets for prisoners'.