Simple Task !!!!!!

How can something so simple be so difficult?

Like many during Lockdown I have added a few pounds on and my 1989 Omega Constellation needs an another link added. I had some spare links and took one to my nearest Omega Boutique (which was now a concession of a major jewellers) who service the watch and was told that they needed a pin which they didn't stock. I called Omega Customer Service and was given a name and number of a jeweller who was an ''Authorised Omega Vintage'' service and repair. A quick call and I was informed that they did not supply parts to the public and to contact an Omega Boutique, is this not where I started?

I have found a pin, spring and tube on ebay but I am not happy dealing with ebay, can anyone point me in the right direction? The clasp number is 1392/012 Stainless Steel.

Thank you.

Sadly they just told me that they didn't have the pin, never offered to order it just gave the watch back. Used the reason that it was a vintage watch!