You're correct about the 5304 model number designation. 82 total were manufactured.
Serials
530-04400 to 530-04431 (32)
530-04474 to 530-04499 (25)
530-04501 to 530-04521 (21)
530-04533 to 530-04536 (4)
Only notable exclusion is serial 530-04500 which is listed in the Ruger Serial DB registry as a .454 Casull yet the firearm serial itself was used in promotional images (pictured below) with a .480 frame/cylinder which could have made sense as a serial registry error in theory, but is quite obviously using a digitally altered final "0" at the end of the serial #. The DB listing it specifically as a .454 Casull seems accurate.
A quantity of 82 Ruger Super Redhawk Alaskan in .480 5rd "5304" were produced exclusively in the year 2008.
All serials listed above are factually correct.
I should have looked at this old post sooner.
A couple years ago I also wanted to see how many of the 5304 were produced and came up with a much different answer.
After going through Ruger's serial number lookup page, starting at 530-00001, this is what I found for the 5-shot .480 model 5304...
530-02401 1 gun
530-03103 1 gun
530-03115 1 gun
530-03442 to 530-03616 174 guns (530-03506 was not shipped or was scrapped)
530-04364 to 530-04431 67 guns (530-04375 was not shipped or was scrapped)
530-04474 to 530-04499 26 guns
530-04501 to 530-04521 21 guns
530-04533 to 530-04536 4 guns
530-04606 to 530-04613 8 guns
530-04627 to 530-05126 499 guns (530-04824 was not shipped or was scrapped).
This gives a grand total of 802 of the model 5304.
Now the question becomes... where are they all at? Were the majority of these 5304's really 6-shot guns? There certainly were a lot of people looking for the 5-shot at that time. Or is it that there are so few double action collectors, or collectors in general who would know the gun they have is different because it is a 5-shot???
More interesting notes... All of the model 5304 were shipped in 2008 except the following...
530-04675 (2006)
530-04678 (2005)
530-04680 (2005)
530-04683 (2005)
530-04694 (2005)
530-04798 (2005)
These six earlier shipped guns would really suggest that Ruger knew of an issue with expanding chambers long before the 5-shot guns were even announced (or were the 5-shot cylinders among the earliest components produced with the perception that a 6-shot wouldn't have enough "meat" between chambers? So in this case were the 2008 shipped guns Ruger's business decision to use up the old cylinders?? ).
Another interesting note... the 5302 (6-shot .480) is also found in their own serial number blocks within production of the 5304's, all consecutive, as follows...
530-04240 to 530-04363
530-04432 to 530-04473
530-04522 to 530-04532
530-04537 to 530-04580
530-04614 to 530-04626
So if anybody hears of a .480 Alaskan between 530-03442 and 530-05126, the odds are nearly 6:1 that it is supposed to be the 5-shot version.
And last note of interest... the very last 5-shot 480 model 5304 is consecutive to the very first .44 Mag. model 5303 which was 530-05127.
Chet15