I am not expert, but the springs seem fine as do the bellows, but that's just from peering at them. I suppose I should take a flashlight to it.
Checking the bellows, with a light, is an absolute necessity. I use a small but very bright LED on a gooseneck that I can get deep in there and check all the folds and corners. That said, there are several options if it has light leaks.
The cheapest and most common solution to leaking bellows is to patch the holes. That is a temporary fix though and it will probably start leaking again within a year or two, depending on how the holes are patched. The problem is that you'll still have bellows that are made of the same worn out material that started leaking light in the first place and it is only a matter of time until it springs new leaks.
The next cheapest option is to replace the bellows with good condition "new old stock" replacement bellows. I have some Kodak bellows that might fit. Then again, they might not. This would involve a complete teardown of the camera, in order to seperate the two frame halves and get the old bellows out and the new ones in. I can do that, but it is not easy -- or cheap. Note on Jurgen's web page how none of the Solidas have new bellows. It would save you about $70 over the price of a new bellows though.
Next option is to have a new set of bellows made, but that is expensive. I think Camera Bellows, in England, charges $80 each for them. Then I'd still have to tear down the camera to get them in.
About the springs: without retensioning, the fastest shutter speeds will be off. For example, in a camera that is supposed to have a 1/500 second shutter speed, the actual shutter speed will be about 1/300 second. With new springs, which you would have to have made, you can get an actual speed of maybe 1/450 second. with retensioned springs you can get maybe 1/350 to 1/400 second. The problem is that tempered steel breaks as easily as it bends and they can break during retensioning if you are not very careful. On the other hand, lots of people can't tell the difference between 1/300 second and 1/400 second.