Pricking iron vs punches

[Tugadude]

There are a number of sites where you can purchase the tool.  Search for diamond stitching pliers or similar.  They make straight ones for lacing, but you want diamond-shaped holes.

 

https://www.etsy.com/listing/695007403/4mm-diamond-point-pricking-iron?gpla=1&gao=1&&utm_source=bing&utm_medium=cpc&utm_campaign=shopping_us_a-craft_supplies_and_tools-tools_and_equipment-tools-pliers_tweezers_and_tongs-pliers&utm_custom1=f75226fa-04d6-4812-9ad1-4753905fdd43&utm_content=bing_352012663_1305120451828985_81570054685939_pla-4585169648612732:pla-4585169648612732_c__695007403&msclkid=677532845b381d4ce6df6cc90763e054

[fredk]

Thats a decent set and price Tugadude has linked to.

I have a pair with 4 teeth (as pictured) and a set with 2 teeth. I got mine off ebay at under £10 a tool but I think they're up to about £15 a tool

Before Christmas I made some note book/diary covers, it took under 5 minutes to go round the edge of each to make the sewing holes. Occasionally I still need an awl, to open up some of the holes. They only come in one size, stitches-per-inch and you can't go more than about 3/4 inch in from the edge. But they are a handy compromise

[Hardrada]

goodsjapan.com has them too:

https://www.goodsjapan.com/leathercraft-items/pricking-irons-stitch-punches?items=100