This may not make a whole lot of sense as far as long and extra long actions but, here goes....
Exhibit A;
Redfield 1-Piece Standard Scope Base Remington 788 <Extra Long Action Gloss>
The 243, 7mm-08, 308, 6mm all take the same stock...So I believe they are all EXTRA LONG ACTION
Exhibit B;
Redfield 1-Piece Standard Scope Base Remington 788 <Long Action Gloss>
The 22-250, 222, 223, 30-30 take the same stock
The 44 Rem Mag. has its own stock, and its own magazine
I believe these are all LONG ACTIONS
The #'s for the weaver two piece mounts are...
#75 (8-40) Thread
#76 (1/2)
I got the scope base info from Midways website...The also offer Weaver bases in Long and Extra Long Actions...whether the holes line up is another story