the ota file should be in /data/data/com.android.providers.downloads/cache
or try this stock recovery: http://d-h.st/pWw (it's not yours, but as close as possible)
rename the file to stock_recovery.img and flash it:
fastboot flash recovery stock_recovery.img
fastboot erase cache
but honestly, this is going to be a futile exercise, if you unlocked using HTCdev, then the /data/preload apps are gone, and if you changed anything else too, the OTA will not work.
I would just go S-OFF, chance cid, and go for international unbranded phone. Or just flash a custom ROM
Anyway, why did you unlock the phone, if you don't want custom ROMs?