Hmmm... my very friendly LGS is listed under Esdevium. I'll go have a chat with the lady minding the store. I usually order from IGUK but they don't have physical copies of TRO 3039, Tech Manual, Strat Ops... much less the FM Mercs books I am looking for.
I do have Sword and Dragon and War of 3039... Sword and Dragon is too warchest-y for me though I do realize I can use it to get ideas. War of 3039 is an interesting read though I cannot seem to get inspiration from it. I guess I just don't appreciate the abstraction done in the Warchest system for a mercenary unit game. If we were playing House army or as a part of a bigger merc unit, I'd use it, but not for a "personal" merc unit.
Perhaps I should ditch the mercenary unit idea for now and go with the warchest system. Easier accounting, more mechs for him to play with, and easier for me to find things for it as well. However, I fear that it'll make it less "personal" for him --- I'd like him to be smart and take care of his mechs, think tactically and not treat the mechs or units just as "items" to be spent to win. We have Warhammer 40K for that. :)