Should be some more responses/advice in a few hours when more people online in North America and Australia/NZ.
On thinking on it some more, maybe the upper end as you have larger than 1 US gallon.
FYI, as I save and reuse my brine, I like using a saturated brine (when salt precipitates out) for brining as then I have a standard with only one variable for corrections on future batches being time.
But, don't use a saturated brine for brine preserved cheeses like Feta, I did that mistake on my first batch of Feta, then tasted after 5 days, yuck
, extremely salty.
PS: Pictures of your new cheese are always nice, next phase for you is aging, the most troublesome.