Yep...the front bushings are made in urethane. Energy Suspension makes a urethane replacement for just about anything related to the suspension that was rubber. I've replaced everything under my car--spring bushings, shock bushings, spring plate pads, A-frame bushings etc... with Energy stuff, and I'm very pleased with the result. They don't ride hard or squeak, and they won't rot with age.
The aftermarket replacement springs are made to the same dimensions as GM springs, so it all interchanges. You can get the poly bushings in black and no one will ever know the difference. The front eye bushings will need to be pressed in, but any frame shop can handle that and it'll cost you peanuts beside buying new springs. Or, if you have a really big vise you can do it yourself! My local guy pressed in all my A-frame bushings for $20. So, since your springs are good, you could probably buy the poly bushings and have them pressed in for around $50. Beats the heck outta buying new springs!
Hope this helps and good luck!