A couple of quarter ounces (not a half) and the rest in silver. Yes, you pay more for premiums, but a quarter ounce of gold is quite a sum of money for a coin. If you had to sell some of your gold you can just sell one fractional at a time. And silver in 10 ounce bars from a known refiner. That gets rid of crazy ounce premiums on silver to counterbalance the fractional gold.
* Don't listen to me. This is what I would do. People collect SO differently. I look at YouTube silver stackers and some of them have the most foolish holdings and foolish reasons to stack. They kind of just list all the reasons for owning silver, which delves into paranoia and conspiracy theories, and validate them like that. I'm usually against anything but bullion when it comes to stacking. Purity always trumps weight, just like with diamonds where the cut, clarity, and color are more important than the carat afterthought that puts a price on its category.
Supposing you get junk silver, now marketed as Constitutional Silver, well the only advantage to this is the relatively high fineness (.900) and its guarantee of purity by the US mint. You pay for the purity. If all coins weighed the same but had different purities, using Gresham's Law, you would accept the highest purity possible and reject the lower karats. If you stack in this way you get nowhere because you have to consider that: your junk doesn't all weigh the same because of wear and circulation. Coins that should have their "book weight" don't have it and therefore any trade in this medium is still subject to weight, and therefore the market would require scales in all shops, or else they would accept the coins at face value, wear notwithstanding, a la John Locke. Culled coins would be the norm again. How many junk coins still have their reeded edges? Not many I'll bet. This silver is subject to culling and slow transactions. If you get them refined and receive currency in exchange for your metals, well that's a different story, but you'll be hard-pressed to find a place to accept them as is without being weighed..
So think about your reasons for stacking. Then buy according to your NEEDS. Do you have an exit strategy? What are your beliefs? How's your future looking? How big is your family? How will a coin help as opposed to a metal? And what I mean by that last thing: if I presented to you a choice between a homemade sterling ingot weighing 16.7grams and a bullion coin (.999) weighing 15.55grams, you would be a fool not to take the coin over the ingot, but essentially they are worth the SAME. One is assayed and struck into a convenient shape and the other is not assayed even though the purity is very very close to .925 fine.
So those are my ramblings for now. Remember, you are buying a convenient form of money/savings, not the metal itself. A copper tube has value but I can't very well use it to buy things. There's this big misconception that silver and gold IS money. They're more like tools, because for a long long time there hasn't been any gold in marketplaces. Don't be fooled into believing that one day every silver coin ever minted will be accepted in the future because that is merely guessing, and badly at that. For silver to be money again, it needs a trusted assayer/refiner for a specified geographical region; weights are secondary. There are no free markets where you can spend your lump of gold - it needs to be identifiable and trusted.
For you it seems that you're comfortable with gold. No reason to change unless you change your beliefs and situation.