You just need a relay with a power lead? I would suggest walking around the junkyards and finding something with a weather proof boot etc. Bonnevilles are great for these 92-99, because they had a relay center on the firewall. I typically go after the fan relays, nice heavy gauge wire, all ready to go.
i have two styles of harness. the one has power feeds for just the ballast, and the other has power feeds for the ballasts and high beams if willing to buy prices will be fair both are fairly new installed in car once until deer took out front bumper