Hi Keith,
there are a few People out there that do axles and the rest of the stuff, if and whether they fit the Job i do not know...
as i do not know the dimensions that are required...
all i know is that a Long time ago, the axels from the Robbe Panther fitted..
here are a few links that might help..
http://shop.der-getriebedoktor.de/kids-1000-axles.htmlhttps://scaleart-shop.de/ScaleDRIVE/Achsen/http://www.rc-hp.de/Achsenhttp://www.ttm-shop.de/ttm-produkte/tamiya-zubehoer/antriebe_achsen/1https://www.lili-modellbau.de/CROSS-RC-Ersatzteile-und-Zubehoer/CROSS-RC-Achsen-und-Achsteile-in-1-12/your best bet would be, come to Dortmund (intermodellbau, trade fair), and speak with the axel experts in Hall 6.. there are a lot of them, and some axels would probably cost you an arm and a leg..
personally I would probably go with the axels from Lili modellbau... I will give them a ring and see what they have to say..
after the phone call, he says that the 1:12 parts should fit as the axel width is about 180mm which is about the same as the Robbe Panther... and the Tamiya axels...
there is also a stockist in the UK..
https://greensmodels.co.uk/collections/axles-steeringyou might be able to get the tires also from there, as they stock RC4WD parts..
http://store.rc4wd.com/DUKW-19-Military-Offroad-Tires_p_2442.html