i haven't heard of anyone around that has the original ROM, but if you download the "unofficial" file and the instructions from
http://www.modaco.com/content/i9x0-o...or-omnia-i910/
this works like a charm. i've been able to flash mine twice now without any problems.
if you still don't want to go that way, the only place that i know that can flash back to oem would be the verizon store. not unless the experts in here can chime in and direct ya better.
good luck