The parts for a K1 (NOT CB750) are:-
77235-300-020 Hook
94001-05000 Nut Hex 5mm
77243-300-000 Collar, seat safety hook
77241-300-000 Hook, seat safety catch
92000-05018-OA Bolt hex 5x18
94101-05000 washer plain 5mm(1 on K1 2 on CB750?)
77242-300-000 Spring seat safety catch
The CB750 doesnt use the safety catch just 77235-300-010 Hook BUT the actual seat complete part numbers are different as well so i have no idea if the lock parts will transpose although it could just be the hook parts that are different as they come with the complete seat
CB750 77200-300-020A
K1 77200-300-030A
Another wierd one is that the CB750 has 7 6x12 bolts and washers but the K1 has 8 (damned if i can find 8 on the picture tho')
Hope that all helps mate and best of luck with parts,
Dont forget
www.westernhillshonda.net but dont believe the database, email them to see if they have stock