They were meant to only be released in the retail edition of 1998/99 but Wang supposedly has said 5 of the 50 were put in the hobby version - I have never heard this before through any source other than Wang and have not heard first hand of anyone pulling one from a hobby box.
I know Select say they issue strictly in order of receipt (which we know they don't necessarily do), however I think the highest number I have seen redeemed is #43/50, so there would not be many at all still sealed in packs....not to mention the astronomical odds of landing one in a retail box (or a hobby one for that matter!).
I doubt Di at select would tell you how many are still unredeemed.