Drew,
Maranello is built by CRG, and uses all the same components as CRGs do (just anodized a different color). We are a CRG dealer and can get any of the parts to fit Maranello. CRG parts unfortunately are very expensive. Some of our own brand components will fit (axles, tie-rods, others), but some parts (front stub axles, brakes, hubs, others) are unique to CRG.
Chains and other engine-related parts are not unique to chassis brand and are readily available.
Slop in the steering wheel is not normal, but can usually be fixed by something as simple as tightening the bolt where the steering hub attaches to the steering column.