Just in case anyone comes across this thread while hunting for the clutch pedal spring for a Volvo 140, here's what I found:

1) As several members pointed out, a few vendors in Europe sell it for very cheap, but the shipping (at this time) to the U.S. is prohibitively expensive.

2) Removing it is an option, but I tried that and I feel that the clutch fork spring tension is a little too light for my personal preference.

3) I ended up making my own spring from 1/8 music wire. I kept it simple, and the spring I made mimics the original, but you could get very specific and come up with your own coil count & angle to dial in the tension.

I hope this helps.