Harc will require a couple of things to make this go smoothly.

First they'll need the box code. This is the No. XXXXX.
They'll also need your name and address. Obvious this one, but many people do actually forget!
Also your engine and frame number for machine verification
The name of your race team and country of participation. (make it up!)
They may also want a copy of your race license or driving license.

Supply as much as you can think of and you shouldn't have too many troubles.

Expect 4~6 weeks delivery from time of payment.