Are there any $1500 tube preamps that that can compare with Tubes4hifi's SP14?

You might consider Tubes4HiFi's SP-13, which is a noval version of the SP-14, uses 6CG7 tubes. It didn't acquire the following that the -14 has and I believe is no longer advertised, but I have owned both and the -13's sound is every bit as good as the -14. Roy may have a few boards left for the -13 and perhaps even a full kit you could get on the cheap. If your choice comes down to either, by all means upgrade the caps and they'll blow you away. 

Since Don Sachs won't brag himself up, I will. My SP-14 has gradually morphed (as time & funds have permitted) into a DS-1, and now we're getting ready to bring it up to his current line of DS-2s. Jupiter coupling caps, Dueland wire and film caps. The DS-1 was a step-level improvement over the original SP-14, which was a very sweet sounding pre-amp to begin with. Don's a delight to work with, too. He and Jim McShane have been restoring H-K Citation amps for years, so he knows a thing or two about great sound.