When buying US Mint proof coins, what is the most common grading?

Say I want to buy a Golden or Silver Eagle, ordered straight from the US Mint's website. What is the likelyhood that the coin will be PR-69 or PR-70 ???

Do I need to buy "First Strike" coins to guarantee this kind of grading? I'd be very disappointed if I spent that much on a collectible, and it turned out to only be PR-65.
Upon a little more research, I found out that NGC listed a census of all the coins they have graded. It appears that a proof coin, graded below PR69 is pretty rare (maybe 1 out of a thousand).

http://www.ngccoin.com/poplookup/

Silver Eagle Proof Coins Ending Soon on eBay:
NGC PF69 Ultra Cameo 1999 P American Silver Eagle Proof

US $88.00 End Date: Tuesday May-22-2012 5:15:30 PDT Buy It Now for only: US $88.00 Buy it now | Add to watch list

• eBay Ending Soon:

  2012-W Proof American Silver Eagle $1 NGC PF70 PF-70 Ultra Cameo Early Releases $109.00 28d 16h 52m

  2006-P 20TH ANNIVERSARY REVERSE PROOF SILVER EAGLE NGC PF69-BLACK LABEL BEAUTY! $217.50 21h 55m

  ★ 2006-P NGC REVERSE PROOF PF69 AMERICAN SILVER EAGLE U.S. COINS ★ $173.50 23h 49m

• 

• Site:

  • About Silver Proof Eagles
  • Silver Eagle Proof
  • Silver Eagle Proof Sets
  • Silver Eagle Error Coins
  • NGC Graded Proof Eagles
  • 2010 Proof Silver Eagles
  • 2008 Silver Proof Eagles
  • 2007 Silver Proof Eagles
  • 2006 Silver Proof Eagles
  • 2006 20th Anniversary Silver Reverse Proof Eagles
  • 2005 Silver Proof Eagles
  • 2004 Proof Silver Eagles
  • 2003 Proof Silver Eagles
  • 2002 Proof Silver Eagles
  • 2001 Proof Silver Eagles
  • 2000 Proof Silver Eagles
  • 1999 Proof Silver Eagles
  • Anti-Spam Policy
  • Privacy Policy
  • Contact Us

• Recent News:

  • 2011 Proof Silver Eagles
  • Silver Eagle Coins ?Club Quick Silver? Home of the 200% Check Match!
  • Silver Eagle Dollar — Distinguishing a Fake from Real
  • American Silver Eagle Coins ? A Smart Investment