OK let me get this straight.You're wanting to get "a super 16 master"from a regular 16 original?First off,how is that done and why?Super 16 is a CAMERA format,not a material to make master internegs from.I don't know of any lab that can get you a super 16 master from a regular 16mm original.The extra room in super 16 is only that small area opposite the perfs where the soundtrack would normally be,not enough to anamorphically "squeeze" the picture and then optically "unsqueeze" it to a super 16 interneg (you keep referring to this as "tape",we are speaking of film here not tape).If you could do this,it would be so expensive that it would be just more cost effective to rent super 16 gear and shoot in super 16.You've got me really confused here.It would be much easier to add a soundtrack to regular 16mm.Super 16 would require a separate track either on 16mm mag fullcoat and you would need a super 16 converted interlock projector to show your film and soundtrack in sync or have a time code put on your super 16 answer print and have your sound mixed onto a synced CD(I've heard of this being done in a VERY few places,specialized films,not much equipment available to do this and what little there is converted regular 16mm projectors done for these few special venues).
There is no difference in regular 16mm stock and "super 16mm stock".What's used for super 16 filming is simply single perfed stock.The cameras are modified to shoot in super 16 by enlarging the gate and polishing down anything the side of the film comes in contact with (rollers and sprockets).
Both Kodak and Fuji discontinued magnetically striped stock about 10 years ago.You can still make a print with an optical sound track,but you're back to square one now,your only option for that is regular 16mm.
The super 16 format came out in 1969 in Europe.It was designed to save money for filmmakers wanting to shoot in 16mm and blow up to 35mm for theatrical release.The aspect ratio in super 16 (1:66 to 1) fits the European theatrical standard better than a regular 16mm blow up.It didn't prove to be really cost effective to shoot in any 16mm format and blow up to 35mm as once yu pay for the blowup,you've pretty much paid enough to have shot in 35mm in the first place.The only time you would save money that way is if your shooting ratio is very high,say 20 to 1.For this reason super 16 didn't really catch on until the fairly recent advent of HDTV with it's 1:77 aspect ratio it fits better and you get less grain.
Now there exists "ultra 16"not to be confused with super 16,but here again that's a camera format not a mastering format.I would be really curious to know exactly how you actually worked before.