Ok i put the ones i made on my home server... might be a little slow:
http://raven.is-a-geek.net/MySQL/MySQL%20Win64%20bin/
They are just the binaries... no installer or such... just replace the files in your MySQL Server\bin directory with these... but of course you should be sure to make a backup (files/database etc) and to stop the service if it is started. I also put md5 files in each folder for the files there so you can make sure they where not corrupted during the download/upload.
I used the Win Svr 2003 x64 Build Env (Retail) platform sdk environment... not sure what this means for WindowsXP 64... but i can easily recompile for that env.
I made several different builds but i would suggest the use of the Max NT 64 build.
The source i used was from version v4.1.15 and v5.0.15. Those where the newest when i downloaded the source... if you want i can recompile with newer versions as well..
Let me know how it works for you!