If it was fitted with the wheelchair motors, you could probably get away with TZ-85s as the ESCs. The newer motors are still reasonably low-current but maybe Victor 883s or something with a similar or higher rating. Battery-wise, go for lipos if funds allow. It's what a lot of UK heavies are using now, with no ill-effects (Alex's recent issue with his budget heavy aside :P) and what I was planning on using too.

Weight wise, the chassis is 3mm steel and weighs almost 25kg. The motors are another few kg on top of that and the original go-kart wheels are silicone filled so are about 5kg a piece. So any international shipping is organised and paid for entirely by the interested party :P