I've had a number of #2 Remingtons over the years, and still have some. Never have seen or owned one that didn't have a half cock notch. The #2 actually had one of those half cocks that truly was half way. Unlike some single shots where the half cock is barely off the block when it clicks in place.
My 1903 Rem. catalog shows the parts breakdown for the #2 and the hammer pictures a distinct half cock notch.