GS,
you're just about to run into the same problem i had with the valve and cable. I obtained a new valve from Australia (I suspect you may have done the same), however the HJ47 uses a unique heater pull cable with an end which looks like a version of a ballpoint pen spring, about an inch long. Every other 40 series from the same era uses a cable with an end turned in a simple double loop, like a lasso. You can't - at least I haven't been able to - make that type of heater pull cable work on the 47's valve. It could be done with some Tig welding and metal fab work I imagine.
The correct heater cable is unobtainium I'm afraid. I've checked everywhere, Australia, Japan, Europe. And I've checked two or three times trying different suppliers. I've looked at a box of 100 cables that Cruiser Parts has in NH and none were in the 47 style. It's just NLA. I've tried to get people in Australia who run wrecking yards to send me a picture of a heater cable as I'm sure they can be found in many a truck there - but I may as well ask them to cut off their left nut for the difficulty it seems to present them. I've gone through 6 wreckers so far and it seems a pic with a digital camera is simply beyond their capability. As a result, i have developed a rather low opinion of Aussie wreckers.
I've been trying to find one of these friggin' 'warm pull' cables for 4 years, on and off. At present I turn the valve on and off by popping the hood and moving the valve actuator arm manually. Hardly convenient of course.
If you find a solution, or a source for a cable, let me now!