Endpoint Encryption

I created a key pair a while ago for use with one vendor a while ago.  I'd now like to use PGP encryption for another vendor as well.  I can't tell from the documentation if I need to generate another separate key pair to use with the new vendor or just send them the same public key I generated a long time ago and it will pick up my same private key.  So do I create a whole new pair per vendor or do I just reuse the existing key pair over and over per vendor?  Thank you in advance!

As long as you still have the private key, and you have no reason to believe your private key has been compromised, you are fine distributing the same public key to anyone wanting/needing to encrypt to you. One of the easiest ways of distributing your public key is by  sending it to the Global Directory (keyserver.pgp.com).