Even the following cards will be a little better:
7600GT (560MHz/700MHz 256MB GDDR3) 8ROPS DX9.1
X1650XT (590MHz/700MHz 256MB GDDR3) 8ROPS DX9.1
HD2600XT (800MHz/700MHz 256MB GDDR3) 4ROPS DX10 (UVD)
HD3650 (720MHz/800MHz 256MB GDDR3) 4ROPS DX10.1 (UVD)
but i don't know if you can find them in AGP ver.
Also you have to consider that the above cards if you run them with DX9.c codepath, there is the possibility to be slower than your X800GTO (400MHz 12ROPs DX9.b) in some games.
I searched Newegg, the only good deal i think is the:
SAPPHIRE Radeon HD 3850 512MB 256-bit GDDR3 AGP 4X/8X HDCP Ready at 89$
http://www.newegg.com/Product/..._-14-102-730-_-Product