regarding the foci armor question, its actually possible to do under the rules, but it involves Weapon Foci.
From the
FAQ:
Q: If you turn a weapon into a focus, but not a weapon focus, can I attack astral forms with it?
A: Under the current rules, only weapon foci may specifically be used in astral combat. This question will be answered fully in an upcoming sourcebook.
Q: If you turn a weapon into a focus, but not a weapon focus, does it still do damage to creatures with Immunity to Normal Weapons?
A: No. It is magic, but it is not a magic weapon. Most spirits don’t have Immunity to Normal Weapons unless they’re materialized or possessing a vessel, but the ability to circumvent Immunity to Normal Weapons is one of the advantages of weapon foci.
note, however, this is for spellcasting focus. Weapon foci, however, do work.Q: If my Spellcasting Focus is an armored vest or shield, do I get an armor bonus against attacks from the astral?
A: No. The telesma of the focus might provide armor, but not mystic armor such as that provided by the Mystic Armor adept power, the Mystic Armor critter power, or the Astral Armor spell.
Note that, again, this is for Spellcasting focusQUOTE (4a 199, weapon foci)
When used in physical combat, weapon foci grant the character a dice pool modifier to melee attacks equal to their force. The character still relies on her physical attributes and skills in combat.; the weapon focus merely makes her more effective. This also applies to astrally percieving characters fighting an opponent on an astral plane. Weapon foci are effective against astral forms and continue to add their Force in dice against such enemies.
An astrally projecting character takes her weapon focus with her to the astral plane. Making an attack with a weapon focus in astral space relies on the characterse astral combat +w illpower dice pookm but this dice pool is increased by the force of the weapon focus. The damage of the weapon is the same on the astral plane as it is in the physical world.
QUOTE (4a 199, foci)
When activated, foci have an astral form and will accompany an astrally projecting magician to which they are bound.
So if you put all this together, I believe a Weapon focus (not a spellcasting, not a sustaining, it has to be a Weapon) focus as a suit of armor will work against astral attacks.
Weapon foci are special, in that they actually have a tangible astral form, more so than other foci, it seems, and you can explicitly bring copies of them along when you project.
The downside is that you lose out on the bonus dice for your foci, because you're probably not bashing people with your leather jacket/breastplate/what have you.
The upside is, you only need a force 1 foci to claim the benefits.
So, to sum up, armor foci don't exist, but weapon foci can still accomplish the same, or very similiar, thing.