They are from a 65-66 273 2bbl BBD. The ends look acceptable to me i would use them if I needed them. I'm happy to ship where ever you want. The head measures greater than 1/4 inch which is the max thickness here in the US for 1st class letters so my guess is that the minimum would be a bubble pack type envelope.
The only time i have seen differences in idle screws is between a Cleaner Air Package (CAP) carb and a non CAP carb for a particular year, year over year I can not say.
As best as I can tell the screw section is 3/16" x 32 perhaps you can check your carb to be sure.
PM me with instructions.