You forget that the Blakists weren't blacklisted from buying material from companies (except Blackwell who had a Dragoon ordered ban on selling to the Word) Also the Word often approached companies to produce Mechs according to their specifications and they also skimmed material and omni pods from the Free Worlds League. Though I agree besides that how were the Blakists able to produce a full line of 6 new Omni Mechs in total secret as well as turning their most fanatical members into basically terminators? Though in terms of raw mterials the lore states that the Terran belt has so much ressources it could feed Terra for centuries to come (of course the question would be if the Belters would be willing to mine so much)
The issue I have with that is there are only so many Mech manufacturing plants out there and if WoB puts in an order for a special model, that's a line that can't be used for someone else's orders and someone somewhere would have wondered why WoB needs yet another Mech run here and one there and one over there when they already have Terra and all those plants.
It would be like me asking Toyota to shut down their US Tacoma factory and produce a special edition just for me. When no other Tacomas hit the market, somebody is going to look into it.
It's just WoB has too many resources at its disposal and too many things going its way and no one seems to care, not even C* ROM, WolfNet, the Capellans or Lyrans, both of whom have an interest in them considering that they are tight with the Mariks.
Had the Jihad kicked off without them whipping out hidden armies of cyborg warriors and Omnis and the ability to fire asteroids at worlds, maybe there wouldn't have been so much objection to the whole thing, but that's not how it went down.
Which brings up a different point: why didn't WoB just hit the Clans? Their whole point was the Clans were THE threat to humanity. So why not just ignore the IS and hit the Clans, even if they just hit the JF, GB, and Wolf Clans? Use their hidden armies and Mechs and cyborg warriors and drive them out of the IS once and for all instead of their temper tantrum. Or bypass the IS and surprise attack the Homeworld Clans. Wipe them out at their base and call it a day. Or hit the AMC in the Chaos March and just beat the Goons to dust, since they are Clan and not to be trusted. Why be coy about it until after the new First Lord is elected? Use the JF incursion during the FCCW as the
casus belli. Even if nothing else that would gain WoB some real goodwill from the Lyrans, FRR, and DC if it shows WoB is willing to help liberate those IS worlds.