Wrong conifg-reg in Rommon, unable to recover

I recently bought an old Cisco 2500 Router and had to reset the password, so I fixed it and configured the router to enter the wrong config-reg at its next reload. When I reloaded it, I just got a bunch of meaningless, redundant symbols and letters. Is there anyway that I can fix this? It is operating using a 10.3 Cisco IOS. –Yeah, old.
I have several other 2500 routers, but do not have any flash cards or a backup on my TFTP server. Help!!?!?!