Kevin wrote: "The postal service here recommend sending you International Reply
Coupons which you can exchange for stamps. Are you familiar with these? How do
US postal rates compare with UK? The blanks I'm sending you weigh 420g.
Here's my response, with comments.
"Just so you can get rolling on your end here's how it's done. Your parcel weighs over 14 oz (the US postage tables still use ounces) but less than 16 oz. The small parcel rate for 16 oz to the UK is $7.20."
420 grams = 14.815 ounces (420/28.3495)
I determined the small parcel rate to Europe (EU) from the table at:
which I have summarized in the link below (US International Small Parcel Rates) with only Small Parcel Rates included.
"Each IRC is redeemable for US $0.60 in US postage. Therefore you should include 12 (7.20/.60 = 12) IRC's."