google -Haynes Repair manual publishing - and you'll find some other places that might carry them.
i googled your exact request and came up with the same manual you did on each site. are you sure the numbers don't match even if it says GM instead of chevy? is it like datsun and nissan??
HAYNES GM AUTOMATIC TRANSMISSION OVERHAUL MANUAL -- In-Depth Coverage Of Popular GM Transmissions Including Rear-Wheel Drive Transmissions THM200-4R, THM350, THM400 And THM700-R4 And Front-Wheel Drive Transaxles THM125/125C, THM3T40, THM440-T4 And THM4T60, Includes Theory Of Operation, In-Vehicle Repairs And Performance Modifications