Go with 234-1056. I double checked and cross referenced and it appears that Denso changed that part number.
FWIW, I looked up the Toyota part number to be 89465-29195, then cross referenced it on Denso's website. I checked the old part number of 234-1051 but according to Denso that part number doesn't exist anymore. When I type that number into www.sparkplugs.com's cross reference system it still comes up as a valid part number, so if they still have those I'm pretty sure they would work too. Tim
PS: to avoid future confusion I changed my original post to reflect the current part number.