Creative Diagnostics has a few rabbit mAbs raised against the C-terminal of human ITK, that they rate OK for FC. Don't know about homology for mouse ITK. Other Abs reactive with mouse exist, but ones we know of don't rate for FC. You can see our listings here:
https://www.linscottsdirectory.com/antibodies?q=ITK follow "More Info" to suppliers' datapages.
There are at least 12 antibodies to murine ITK claimed fit for FC on the market. If you struggle finding one that meets your requirements, we can help.