I don't know about the RMU prices and standards of living, but an armourer was not a simple blacksmith - they were a specialised craftsman with fairly high wages, and were usually very specialised (several people with different specialties worked on a single suit of armour, each doing a few - or even a single - pieces).
Armourers were high earners among the craftsmen (in other words, after expenses, taxes, guild and church tithes and maintenance of tools and workplace, they still had a fairly comfortable standard of living. Of course, journeymen (which had not reached the degree of expertise required to be part of the guild and earn the title of 'master') earned much less, scarcely more than an apprentice.
I don't know how it translates in the RMU economy, but Harn (which is kind of my game reference of silver-based economies in medieval-like game settings) quotes a weaponcrafter (the armourer above) as earning ~108d per month in wages (i.e., being bonded masters, they do not have to pay for room, board and supplies, but they have to pay for their own tools. This was the most favourable position). By way of comparison, a suit of mail costs more than 1500d.