The numbers aren't right in my pocket, but there's always
www.toyodiy.com for things like this, no problem. The head gasket is indeed 11115-16111. If you can budget for it, I would strongly suggest a complete engine gasket set, since you'll want to replace a lot of other gaskets at the same time, and we can't get most individual 20V gaskets outside of the kit.
04111-16211 - $223.13 - gasket set, engine overhaul, 20V Silvertop
11115-16111 - $35.98 - Head gasket, 20V Blacktop and Silvertop
These are saved on quote number 51052 for the time being. Unfortunately, I can't get the head bolts. I have seen some references to other Toyota head bolts being acceptable substitutes, but I don't remember where exactly. It was definitely somewhere on one of the MR2 forums.