SWIM had a minor thought when looking at HCL gas generator plans. Assuming CaCl will not interfere with a reaction, and AFAIK no (or extremely little) pressure is created when generating HCL gas, could one just place CaCl into a bottle with the chemical to be gassed, and then drop in aqeous HCl by any means (funnel then quickly lidding, or safer, using a syringe and a port). The CaCl would eat any water to begin with which is good since HCL gassing is used in water-free situations. This keeps the rxn dry. The water from the aqueous HCl gets eaten by CaCl, leaving Hcl gas to come out of soln. The bottle is simply shaken.
Any thoughts? Don't flame me, there's probably a hundred good reasons why it wont work, but maybe someone can use this to model a safer way. SWIM just likes the idea of safely putting all reactants in one container and shaking rather than having ventilation.
Edit: In a dream SWIM's friend just attempted this with methyl ethyl ketone + benzaldehyde + cacl + aq. hcl in a bottle purely as a test, at 5C, shaken hard, settled to contain an oily layer. So unless the hcl reacted with the BA in an odd way, the 'safer' gassing way worked?