I have a 78 Dodge Aspen, One of my leaf spring are broke and I have a set of springs from a 74 Cuda. I was just wondering if these might fit or what I would have to do to make them work and if it would be worth it.

if you're just using one of the support leaves, I wouldn't see why not. If you need the main, you'd have to measure them up as far as length and end sizes.

F body and late 70s B body used an Oval front eye and bushing. The Cuda will be a standard round eye.
If you main leaf is broken, you cannot use the Ebody.

The main leaf is broke. It is broke where it mounts to the front.

That is the common place with those...
There aren't many left in the boneyard.
you could try car-parts.com
Or put an ad in the parts wanted section, I bet 5th av. springs would bolt in..