The big question is how much extension you need.

A lot of 8x10 cameras top out at about 28" or less. If you need more than 32", your list will be pretty short, and the top cameras would probably be a Wisner Traditional (40"), the Canham traditional (36", oh to have the money!), and the Lotus (37").

If your Agfa is one of the cameras with the 36" bellows, precious few man-portable cameras will have more bellows. The only way I know of to exceed 40" in a "field" camera is to use a modular monorail system and string together multiple bellows and standards.