MJB, the US Govt have forced all tv stations to tx in HD - well, their version of HD !!!!
With the costs involved and the current economic probs, many local tv stations are starting to share a helicopter resource, thus creating some (well) used machines with gyromounts.
So - a lot of SD mounts around which would need a little mod to be able to carry an HD camera - depending on whether you use slip rings or not.
Hasn't someone in NZ got a Cineflex V12 for sale ? This could be modded to carry a small HD camera. Nice unit - great stability - and probably weighs in at less than 40lbs.