I purchased a new engine harness from M&H Electric and knew that I was also going to repair my instrument panel harness. I asked if they would sell me about ten sockets along with the harness that I was buying and they were nice enough to oblige. I don't know if they will just sell them directly but you can always ask. You might also try the other harness makers like Painless.
Good luck!
Bob
Good luck!
Bob