I gave up on the Convoy C8 because of that Alu pill I recall reading previously that other C8 pills do not work in the Convoy, as these say they are for the Ultrafire I’m guessing Convoy owners would still be out of luck.
I see on both sites the picture is of the same pill, I’m guessing that both sites belong to the same seller. How are they to deal with?
Not out of luck at all. I bought one from each of those links after reading reports that they fit the Convoy C8 perfectly, and can confirm it. That’s why I have a spare. They where first sold as copper pills but they changed the description after BLF members pointed out that they are brass. Here is the thread: Copper? C8 pills for $4.30
Same seller. The description changed to brass on both sites at the same time, and my two showed up the same day with the exact same packaging. No hitches with my order at all, the pills are so far my only experience with them.
No, the description at GB is wrong. I know, hard to believe. 
The GB one fits Convoy C8's perfectly. It fits the Supfire M2 also, perhaps sits a hair higher than ideal. It also fit in deep reflector Ultrafire C8's (LightsCastle & ebay) I have but the reflector almost touches the pill, might work with a thin star and thinner centering ring. It doesn't seem to fit regular UF C8's but I only have the Tangsfire C8 from Tmart to test, drops right in without threads touching threads.
Someone posted a review at GB stating Convoy compatibility already.
Great, thanks to both of you for the updates, good stuff to know. As my C8’s have become shelf sentinels, perhaps these could bring new life to them.