Hmmm.
I have a plan for an old Puffer in MBoats (cardboard hull over deal formers) - it has a sorta smoker using (I seem to remember) smouldering cotton wool soaked in baby oil or similar (!)
But it has a home-made vane fan which could easily be replaced by a recip with a big piston and variable speed
Having said all that the mag in question is in a repository, quite safe: so not easily accessible
not difficult to make a large piston air puffer - its not a compressor - just a pusher; so the piston seal could be nothing or a layer of foam plastic on to of whatever the piston turned out to be.
I would probably use a sharpened tin can to cut a chunk of thick PP foam and call that the piston!
The tin would be the cylinder
[Carruthers! DON"T use a corrugated tin for the cylinder!]drawing-pin valve on the piston for air admission, maybe no valve at all or a shuttle valve (again foam) in the delivery pipe
I'm a great believer in trying ideas for free, if possible
Sketch possible, but not till tomorrow (Aus time) as I know the internet is not working at home. I'm thinking big tin, big flexi pipe for delivery, short stroke using eccentric and spring return. variable speed drive for the rate-of-puff
worth a try,
andrew