Almost all attachment parts
(wheels, brakes, bearings, axles, hubs, seat, steering wheel)
are more or less standardised
means there are different sizes and you need the right one for you and/or the kart,
other than that they're 100% interchangeable without any refabbing.
There are a few parts that are not or not necessarily let's say..
like removable crossbracing and nerf bars,
sometimes the engine mount is chassis specific too.
BUT even that can be dealt with easily..
there are universal engine mounts that fit about every rail size and distance
And there's a good chance you find nerf bars that do fit with only minor adjustments of the nerf bar itself (if at all)
Only the crossbrace
(see the two tiny stub tubes on the far rear?.. that's where the crossbracing and rear bumber would mount to)
is likely going to be a DIY part..
but the good news for that is. the tubing clamps are again standardised and all you need is a cut to size length of proper diameter chromoly tube
(I think either 30 or 32 mm)
so no big deal at all.
So no.. nothing to really worry about.
'sid
PS would you measure the rear axle diameter for me please.. that looks like a metric 35 or 40mm axle..
if it is, we can narrow on in on the manufacturer more easily
PPS check righettiridolfi.com if you need any part.. they make about every kartpart there is.