I don't think so. First off it looks like the pulley’s sieve fits a rope, not a clothes line string. And it also has a backlash tang; I've never seen that on a clothes line pulley. It could or might be a barn loft pulley, or something like that, just a guess.
Don't think this would be applicable to barn use (could be wrong)...too small and wouldn't stand up to the abuse...Raised on a farm so I'm offering an opinion based on experience, and not trying to be argumentative
The fact that its wooden kinda relegates it to a more delicate use...
Looks like a combination of two things, that leads me to guess that it is pulley to assist something like a pocket door, possibly very heavy solid wood door. Whatever it was used for it was indoors and concealed within a wall.