Sunday Times Cryptic 4908

[NeilMunro]

Very grateful for all help with these clues please.
5ac: “Joints provided in some prosthetic limbs feel stiff at first (7).”
6dn: “Large copper in uniform heading for bogus judge’s study at night (9).”
10ac: “Parties entertaining northern banker throws (11).”
26ac: “Look around and be curious, dear fellow (3,4).”

[Lie-in King]

5a Spliffs - 'if' (provided, in) 's(ome) p(rosthetic) l(imbs) f(eel) s(tiff)' (at first)
6d Lucubrate - 'l(arge)' + 'Cu' (Copper, in) 'U(niform) b(ogus; heading)' + 'rate' (judge)
10a Disconcerts - 'discos' (entertaining) 'n(orthern) cert(ainty; banker)'
26a Old bean - 'lo' (look, around) + anag 'and be'

[NeilMunro]

Many thanks Lie-in King!!!