That is an odd size. Generally you want to be working with standard dimensions so they work with standard formats. Anamorphic usually means that the image is squeezed. Sorry, you have not given enough details about what you are trying to do to point you in the right direction because I'm not sure how you would use an anamorphic comp of that size or how you would play it back.
Standard h.264 frame sizes:
The standard frame sizes are down the page a bit.
Yes it is an odd one - its for an in-store display, so doesn't fit into the usual broadcast /online requirements.
the client has requested a square pixel version- which is fine, but also anamorphic which obviously squeezes this image.
going from 16:9 to anamorphic(4:3) makes sense to the usual format but for this I am asking the client if they rotate the image and
deliver at 90 degrees, so do we squeeze along the horizontal/vertical...?
thanks for your response
You are going to have to contact the folks that make the gear that is going to playback the video. They will have specifications. Unless someone on this forum has used the same system and remembers the proper settings, formats to render to and other specifications the only reasonable way to know what to do is to ask the manufacturer. BTW, you will probably have to use specialized compression software to render your deliverable if they want MPEG compression because AE and the AME will resize your render to the nearest standard size.