Mikey, the one's that fit the aesthetic best IMO are these:
https://www.ebay.com/itm/Jewelry-Tr...702?pt=LH_DefaultDomain_0&hash=item3375105116
Keywords: Pirate, Chest, Gothic, Jewelry
They really look great for 1:6 scale without looking like cheap trinket boxes!
I've seen these come in a variety of sizes, Biggest are around 8-10 long, 4-5 inches high, smallest are around 4 inches long by about 2/12 high. I love the overall shape and weathering on these (most are around 50 years old). Just make sure you look out for missing pieces, for me I have to have all the lion heads in place plus the center clasp.
It's funny how creative minds think alike.
Good Luck!