amd's website is pretty accurate.
I've replaced a ton of metal on my 69 GTX since 2020, I bought a few pieces at a time and sometimes an item would run out of stock when I was getting ready to order.

For the most part I just started checking the website once or twice a week until they showed up again, but there was one item I did drive over to Roseville Moparts
to buy because the item was on sale there and I could get it the same day.

There are some dealers under site sponsors but not many who will respond in the forum areas anymore.