Local clutch rebuilders are not as common as they once were, but if you google 'automotive clutch rebuilder parts" you'll get a couple of hits.
But now the challenge, and you may be very aware, but if you have decided to grapple the task of re-springing your clutch (I assume this is a 'Long-Style' unit?) for rebuilding or for changing the clamp-load pressure value, then again as I often say: "you're the new engineer"; and 'you're' going to have to establish the suitable replacement components.
This process works very similarly to selecting valve springs for one's cylinder heads: this via establishing the clutch closed position spring installed height and desired spring load value, clutch open position spring installed height and desired spring load value, (don't forget this value is multiplied times the number of springs!
), then the dimensional fitment requirements within the hat and the pressure ring locating receptacles and so-on.
I'm assuming that the O.E. for your unit doesn't offer what you're looking for, and is the reason you're searching elsewhere; but the parts suppliers, other than the manufacturer of 'your' unit, though they may very well have what you might need, are not going to be aware of the proper components in order to acquire your requirements.
And as another note, I have at times found cylinder head valve springs suitable in certain instances.
Scott.
