Check EBay, but be warned: They are very pricey. I picked up a turbine powered Wessex and pilfered the nose out of a Revell H-19/S-55 to convert it back to the piston engined version for less than the H-34 goes for on EBay. I've had two of these kits before. On both kits, two of the rotor blades are straight, the other two are badly warped. I destroyed mine trying to straigthen them out, so I'll have to scratchbuild new blades. If you are interested, I could be persuaded to part with mine for a reasonable offer.
JR