I'm gathering you're simply looking for an idea of where to start as far as integer values for your weapons and armour? Well, in Rebirth, every tangible object that can be worn has at least some protection, albeit extremely small for basic cloth clothing, such as a point or two for most normal damage types (blunt, blade, shock, cold, heat, etc...) all the way up to your plate armours which might have 10 or 20 points defence against things such as blades. When deciding the basic attach values for common weapons such as knives and swords and such, I started with the base values used back in the old AD&D rules, where a basic dagger had a weapon class of about 4, up to your big swords that were around 8 or 10. However, Rebirth is hugely a skill based game, so those values are just the base. Also, keep in mind that, I believe by default, the damage absorbed on a strike is a range from 1/2 the armour value to the full armour value.
I don't mean to get into a medieval armour debate or anything, but technically the term 'chain mail' is a misnomer, as it is simply called 'mail' or 'maille'. This armour, in fact, protects very poorly against blunt weapons, so traditionally they wore kinds of padding under their maille, such as brigandine armour. I realise you were just giving examples quix, I just thought I could put in my two cents.
Lash, any values you go with, in the end, are just arbitrary numbers. The only thing you really want to be care of is choosing a range so small, you end up backing yourself into a corner when designing weapons and armour, or numbers so large that it becomes difficult in getting a feel for exactly how good an item really is.