I assume that even if the 3 non-identified were close to exact replacements, then they probably still take the same motor.
I never assume but in this case I believe you are correct. The motors are cheap on Ebay but I believe Grainger and other supply houses also sell them. One item to check for on the little 24 volt motors is the gear on the shaft. Many times the little gear will come loose and the motor will run but will not open the valve. If you run into that situation many times you can solder or press it on tighter to make it work. This is mentioned just for your future info.
Also those small motors are also available in 120 and other Volt versions. While rare always make sure it is the 24 volt one you are ordering if your system is 24 volts.
Here is a link to a downloadable info sheet on you type of valve. This covers many versions but always look at the model number you have for accurate info.
http://customer.honeywell.com/techli...0s/60-2133.pdf