I don’t have an answer to this but for some piece of mind, have you called you local OB or the phone number on this thread:
https://omegaforums.net/threads/swatch-group-usa-ordering-information.134228/
I have ordered buckles and bracelets from my local OB and had free 2-day delivery.
I also don't have an answer but I noticed on Omegas official website if you select a watch strap the charge $50 for a stainless steel buckle. Switch it to yellow gold and it skyrockets to $630 😲
Is this the going rate for these?!