Construct these box prints yourself. If you choose to download the file, you'll need some double sided tape, scissors or a knife and a printer.
If you order by post, I print them on A4 180 gsm HP everyday glossy photo paper. I tried a few different papers and this worked the best. It is stiff enough and the ink doesn't come off when folded. I include a bit of double sided tape but you will still need a knife or scissors.