If it is a fibre composite then I would expect that you would use an aluminium insert. If its brick carbon like an electrode it can be tapped, just the strength will not be very high.
MY10A was a code on an old drawing for something similar.
I have now found the company that supplied that material and will get the correct spec. I'll post the exact spec. At least now with your help I should be able to make an informed decision!
I'm guessing, but that looks like an electrode type of compacted material. It will tap, you will need to go slow and be careful. The material will be really soft. Luckily the graphite lubricates the tap. I dont know what metal its impregnated with but it should not be a huge issue. If the material turns out to be very abrasive to the tap you can use carbide.