There are two released versions of the 7800 BIOS. The standard NTSC one with the Atari logo; and the one with the built in Asteroids game that is both NTSC and PAL but usually labeled as PAL only.
There are three prototype versions. One is an early version of the standard NTSC BIOS, one is a version of the standard NTSC BIOS and includes a built in copy of Pole Position and lastly there is the one that is an early version of the BIOS with the built in Asteroids but supports NTSC only.
There are also three newer dev BIOS releases but I don't know if you care about those.
Currently we only support the 2 standard NTSC and PAL dumps and the asteroids prototype bios. Do you have the checksum for the older ntsc bios version? I'm wondering if its the same as the checksum commented out in a7800.c