My 682 is 32". I gather you meant, oldman1949, that the subgauge barrels from Cole are not available in that length. However, I could probably live with 30" subgauge barrels if the handling could be set up nearly the same. The subgauges are not nearly as important to me as the 12 anyway, so if I cannot get satisfied with what is available I may just get 28 gauge and .410 barrels for the 687 SP II Sporting and go with that. At least everything would be nearly identical in the subgauges that way. Maybe some playing around with weights in the butt and on the barrels could make them closer approximate the 682. Not equal, but closer.
I have been shooting the 682 pretty well this spring, and have won my class in a couple of pretty decent sized shoots, so I might should just stick with it for awhile anyway. Thanks for the information, everyone.
Stan