grades are not marked, the date code is on the left side of the barrel near receiver (see link) those marks are inspector marks. I believe the only want you tell the grade of a 511 is the sights.
By the serial number and markings on the barrel.
Markings typically include model, The Remington trademark, date of manufacture, test marks, inspectors, and proof mark. In some cases it may be a factory repair mark, or indication of Magnaflux testing. See the link below for an illustration of barrel code markings. Note these are for REMINGTON only.
http://remingtonsociety.com/rsa/questions/barrelcodes For date markings, the forums on the site for others.
Lookup of the barrel date code markings on the Remington Society of America, manufactured date link.
There should be markings on the left side of the barrel by the proofmark like K or an E and Remington has a year chart on their website
http://remingtonsociety.com/rsa/questions/barrelcodes
The Remington Model 4 was made from 1890-1933. Check the barrel on the left side for letter markings (2 letters, just forward of the receiver) that are the code to date barrel was made. You may also check with Remington.
Remington did not make the A5. From 1906 to 1947, Remington produced the Model 11, which was their version of the A5. However, the barrels were not made by FN (Fabrique National, Herstal, Belgium) Please check the markings on your gun and repost your question. If it is a Remington, Remington Customer Service MAY be able to help- but Remington guns are usually dated by a 3 LETTER code on the left side of the barrel- and if that is not the original barrel, all bets are off.
http://remingtonsociety.com/rsa/questions/barrelcodes or try the forums and ask.
I don't know about the Super Deluxe name however they do exist. I currently own a black stocked version with white diamonds. The receiver is chrome plated and the barrel is nickel. I checked the serial number (2311XXX) a while back and believe it is mid 1960's production. Wikipedia indicated the nickel version was Brazilian but mine is stamped Remington. Other barrel markings are "BY", "REP" in parenthesis, what looks like an iron cross and and the number 70. Buttstock is also marked Remington USA.
Impossible to answer without a DETAILED description of ALL markings, gauge, finish, condition, barrel length, choke, box, accessories, papers.
Four of each except in the 03 Springfield. I believe they had two.