I've found a couple of ROMS for you sntaylor, unfortunately not stock MH1 which I thought I had, but Djembeys stock, pre rooted and deodexed version of the "full fat" ROM.
Here it is :
LINKS NOW REMOVED, but I still have the ROMs
I'll leave these public links up for a while for anyone who wants them, but I will take them down after a while, it is Drop Box and they don't appreciate you using them to host files.
I know I have MH1 stock somewhere, but for the life of me I cannot find it. Your request may have inspired me to do a complete sorting out of my lap top, USB sticks and external hard drives. I have multiple versions of all sorts of family photos, music,ROMs, Videos etc.etc. Nearly 2TB of data about 500MB that is actually needed. Most of it is duplicated stuff, and all of it is on my two external hard drives. I am usually quite organised but I have gotten into a terrible habit of sticking currently needed files on my phone (also has nearly 10Gig of crap on it) and/or a USB stick I have on my key ring. Then backing up every month. Result: slow nearly full laptop and repeated files often in more than ten locations. Nightmare.