Here are the statistic I have come up with for a Marauder Chariot. I basically used the guidelines on pg 121 of the main rulebook.

Chaos Marauder Chariot
Light Chariot	M	WS	BS	S	T	W	I	A	Ld	Int	Cl	WP
Chaos Marauder (2)	4	5	5	3	3	2	5	2	8+1	8+1	8+1	8+1
Chaos Steed (2)	8(6)	4	0	4	4	2	4	2	5	5	5	7
Models Per Unit: 1-4 Chariots Points Per Model: 300 Weapons: Hand Weapons Armour: Heavy Armor and Shield Steeds have Barding Options: Scythed Wheels +20 points One May have: A magic Standard 50 points A Magical Instrucment 25 points Any Rider May have: Additional Hand Weapon +2 points Double Handed Weapon +4 points Halberd +4 points Bow +4 points Crossbow +6 points