Coil spring lift or Spacer lift?

I need to lift an 84 Buick LeSabre to clear oversize wheels. I'm wondering whether to go with buying new oversize springs, or just buy a spacer kit off eBay. I'd probably prefer to go with new springs, but have no idea what to buy. I've heard of people installing truck springs, or cargo springs.. I don't want to play a guessing game buying springs on eBay as that could get expensive. If anyone has any info that would be great.