I paid for mine long before it was shipped on Monday the 25th, got it by standard mail, aka parcel post, on Saturday the 1st.
Brownell's sells the scope rail for the same price as H&R sells it
with the hammer extension, if you want one from H&R, better get it ordered quick, they're gonna close up shop for 2 weeks sometime this summer.

They usually get stuff right out, but not always, took me a month to get 3 rails last year, had to call em back and and reorder a couple stocks within the last month.

Tim
EDITED: I just realized I'm out of scope rails, went back to Brownell's, once you put the rail in your basket, it shows including the extension. If you order 1 or 2 rails, you can get by with $4.25 shipping, but if you order 3 or more, shipping is over $9.