[pawpawdiv9]

Sir you may want to look at auctionreport or look at oldcardboard for auction shedules. There are many at any given time. REA, Heritage are good starters, but there are so many. Also, be aware of buyers premiums and s/h charges too. Have fun!!
I know several Mantle collectors on other forums that deal with high-end Mantles. If you need help just ask. I recently consigned my Mantle collection, and is almost completly sold thru Sterlings. I kept my 51B & 52 RC's for my RC colllection.

[Hofcollector]

Heritage and Mile High are great auction houses. You can try Probstein on Ebay as well. They deal a ton of high grade vintage. I sold them a lot a few months back with several high grade Mantles including a '54 Bowman PSA 8, '56 Topps SGC 88, '59 Topps BVG 8, (2) '65 Topps SGC 88 and a few others. There's a few guys over there that do a ton of shows.