It is difficult for anybody to claim they know exactly what you have - unless you have a head off. I've seen countless flatheads with heads that came from any of the 39 - 53 24 stud engines, so you can't always rely on the heads.
With that said, if it doesn't have a '59' on the bellhousing and a large 'A' on the head (and it hasn't been reconfigured sometime in its lifetime), that is USUALLY a 39-41 or so Ford 221 cubic inch engine.
That is about as close as I can get without seeing what you have (with a head off of it).