SOS! Lulabelle needs help!

So, for nearly five years the lovely Lulabelle has been trundling round the festival circuit serving tea, cake and smiles... She is in desperate need of a 1200 gearbox that is compatible with reduction gears....I've had one on order for weeks and they've just rung to say they can't get one...

Can anyone help us? She's been struggling along but I know the original is on it's last legs and probably won't last very much longer...

If you know of anyone that might have one or could source one for us it would be so much appreciated...