I bought this rusty Gjermundbu helmet at Hastings last week and after wire brushing and repainting the thing I'm wanting to add a 'Y' type chin strap to it so that my nose won't get squished if I get a blow to the nasal/spectacle.
Does anybody know where online I can get dome rivets made of carbon steel (i.e. steel that rusts) that can hand peened with a hammer without being robbed blind on shipping costs?
The rivets hold like the one depicted below with dimensions approximately d1=6-8mm, d=4-5mm and l= 15-20mm

