Under Special Ammunition in AU, under Armor Piercing Ammunition:
Armor piercing rounds are constructed of teflon, Kisenite or some other materials that are strong enough to penetrate hard substances easily.
Adds 1d6 to the damage capacity of the average round and is +2 to penetrate armor (this means an A.R. of 15 is an A.R. of 13 in regard to this bullet); usually reserved for larger calibers. Bullets made of Kisenite are considered AP rounds and are +3 to penetrate armor. Half the bullet's damage is expended on the armor and half strikes the person inside the armor.
Strangely, the price is ommitted (by mistake, I assume) from both the old version of AU I own and the newer Revised edition. Pricing would be somewhere between the ready-made price for AP Shotgun shells from the Weapons Hardware class, which have the lower AP effect and are $80 per 10, and the Kisenite Arrows, which are $2000 per 12. They will wind up not cheap, to be sure.
I would hope that the Alien Education, Skills, and Knowledge rules from AU: Galaxy Guide (pg 190) would be used instead of the HU2 rules for Alien skills, as those newer rules were developed specifically with a Space-centric game in mind. If so, there isn't a table (you just pick your Skill Package), so that part of the character, at least, shouldn't be random. In a normal HU2 game those rules wouldn't be balanced (part of the trade-off for the extra Alien powers and gear is the more restricted Skill choices), but in a game where everyone is an Alien, I think they are a much better fit.