My spare anchor is a 7kg Bruce "clone" and looked like it might fit the bill.
|Starboard view of smaller "Bruce"
I drilled a hole through the forward part of the shank to align with the holes in the Ballad anchor mount and used a 1/4" bolt to hold it fast. This will soon be replaced by a spring-loaded pin to make it a one-handed job to undo.
The original bronze anchor roller was replaced with a larger Delrin one, with deeper and narrower groove to hold the shank better.
|Port view of smaller "Bruce" (wing nut is on temporary holding bolt, soon to replaced by a pin)
|Anchor Lock, raised up on 3/4" block, and bolted through the deck.
|Aft view of anchor lock.