It's Elvis Presley week at Graceland and in honor of the King, Mattel has issued limited edition Elvis and Priscilla Presley wedding-day dolls.

"It's been a year in the making," Priscilla tells ET's Mark Steines. "It's unbelievable what they've done ... even to the little boutonniere on [Elvis'] lapel and the tiara I have on my veil."

Forty thousand of the dolls will go on sale with the first 200 hitting the shelves at Graceland today. But only one will be autographed by Priscilla. It will be auctioned off to benefit Presley Place in Memphis, which provides housing, career and financial counseling and other tools to help its residents break the cycle of poverty and regain independence.

Elvis and Priscilla married on May 1, 1967 at the Aladdin Hotel in Las Vegas. They managed to keep their wedding a secret from the press -- even going so far as to use a decoy fiancé whenever Priscilla would go for a dress fitting.

"We knew if it did get out, it wouldn't be the wedding we wanted, it would be a circus ... We could never pull that off today, never ever ever," she says. "We flew from Palm Springs [in Frank Sinatra's plane] in the early morning hours. We did not sleep all night long. We were just comatose because of the excitement."

They were joined by their families and friends and, while their vows were traditional, Priscilla remembers that the word "obey' was taken out of the ceremony.

Mark asks if it was something that Elvis wanted, but Priscilla laughs and says, "I didn't want that."

For more info on the limited-edition dolls and the auction, click here.