Sorry, not what you want to hear, but a few years ago I sold about 200 rounds of factory 300 Savage ammo, and gave away 400 reloads, and a few hundred brass. An elderly friend of my mother's son had died, and she asked me to dispose of his "gun stuff". The last remnants of that hoard was the 10,000 or so primers that I recently sold here. So, you never know by asking around, and this is a good place to start. When they start having them again, gun shows may be a good option.