Small Pendulum (up to 30ft LOA) and Medium Pendulum (30ft to 50ft LOA). There was also a Big Pendulum, but I think only one or two were built, one of which went onto British Steel.
I've had SibLim's requirement in mind as I've been thinking about Weaverbird's gear. I don't think I've got anything amongst the old Gibb parts, liberated when the factory closed down, that would be any use to you, and I'm certain that the very last thing you need is a Hasler trim tab gear. What you're going to need is a trim tab on each rudder, using standard dinghy rudder pintles and gudgeons; a crossbar linking their tillers; and a vertical axis vane with a simple toothed wheel latch (as I'm making) that can be cord-linked to the cross bar. Then (and here's the fiendishly cunning part) it is the work of a moment to reverse the linkage so as to be able to try the gear in trim tab mode with direct linkage, and in auxiliary rudder mode with a pair of small blocks reversing the direction of the linkage.
You aren't going to need the gear until the autumn, and come the autumn, I, as a Country Member of the Siblim Club will have tested my gear and will be in a position to make you a suitable latch gear.