What colour is it ?
If you can scrounge a few cms from someone then there's an iron heat powder glue that is excellent for repairing fabric with a hidden rear patch in the same material.
Failing that, if you have a pocket that you can sacrifice the inner pertex from (and patch that where it won't be seen, you can create a small tab pocket from the material.
If you take it to the local repair shop, the kind where someone capable turns up trousers, curtains, etc., they might offer to secure stitch across your tear and you could always sew a badge of some kind on top. You can even print your own out on your computer printer, in reverse, iron it onto something suitable and create your own 'patch'.
You're unlikely to hide the repair unless you make it a feature, like a pocket, a label, that kind of thing.
Sorry, I don't think I'm actually solving your problem though.
M