SGC slabbing as authentic? Question...

[jchcollins]

I posed a similar question a few months ago on a different thread, but didn't get the detail I was looking for - so indulge me, here goes again:

I'm considering sending the '56 Mantle I've had since I was about 14 off to SGC to get put in a slab. Forget PSA, I have nothing against them - but I'm not waiting 6 months plus to get it back. The card has some paper loss on a corner and has already been deemed "altered" (or their equivalent of it, anyway...) by SGC once, probably 10 years ago. My questions if I send it in again:

* I would just be looking to get it in the slab for preservation purposes. Can I tell them to just not grade and slab as authentic? If so and they notice something about that one corner again, would they say it's "Authentic Altered" on the slab? Or just "Authentic"?

* What would ballpark cost to slab just this one card and turnaround time be, do you think? I don't have any kind of account with SGC, and would probably insure this for $500 if I were going to mail it otherwise. The card is not perfect, but would probably be a 3 or 4 without the corner isssue and has a lot of eye appeal, no creases.

Thanks
-John