Do-It / Hangtab.com is my preferred Hang-Tab vendor (unline U-Line, they have _folding_ hang tabs). I use R-52 hang tabs which are out of the way until you pop up the tab if the retailer needs it.
A deck of cards weights 3-4 oz if you include the case.
The possible hang-tabs I could have used:
1.375 x 1.375in
2.5 x 1.5in
R-51 / R-57 Imperial Metric
2.5 x 1.5in (W/H)
I went with R-52 since it has the smallest footprint.
They have an online store here:
But the R-52 product isn’t available online. If you call them, they will see if it is in stock and you place the order over the phone.
Uline option (but don’t fold over) are at: