Quoted from WizardsCastle:
Is this the stuff? Google gives me 99% American sites, but I did find this one:
Also, do you find it to be a good match to the stock inside walls, so I can just touch up a couple of spots?
Yep, looks like it.
You'll have to try and see, the condition of your remaining black will also determine this, especially if it's faded or slightly dirty. It's easy enough to put on with a foam brush you could do the whole inside wall for a good finish.