I need a broken Famicom cartridge

[ClassicGamer]

I just opened up my Supervision 76-in-1 to get the Famicom-to-NES adapter inside. But now I can't use it, because the bare circuit board wobbles around in my FC Twin.
I'm going to hack up a Winter Games cartridge to put the adapter in, but I need a Famicom cartridge to put the Supervision board in. Does anyone have an empty or non-working Famicom cartridge that I can put this thing in?

Or just a Famicom to NES adapter. That would work too.

[MLX]

I do have a bunch of dead carts. But unfortunately shipping cost a shitload here so I doubt you'd be interested. PM me if you would still be interested.

I have different kind of cases btw (TV Game Cartridge, old small ones, newer small ones)

[ClassicGamer]

I'd prefer one that's white, because that's the colour of the original cartridge. But it doesn't really matter as long as it can fit a 76-in-1 board, which looks pretty big, but I don't know how big a normal Famicom board is.

[ClassicGamer]

Does anyone else have a cheap Famicom cart?

[Pepper-98]

I have a Mother cart that has the inside tabs broken.  You need something like tape to keep it closed, but it's fine otherwise.  The only other thing I have are Waixing carts that are easy to open.

[KAGE-008]

I have two dead carts, but I can't remember where I put them. One came with a Keyboard famiclone and the other is just a 99999999-in-1 with 1st gen Famicom games.

[ClassicGamer]

How easy do you think it would be to modify a Famicom cart into a converter? I'd rather not do it at all, but I can't find a Famicom-to-NES converter anywhere.

[ClassicGamer]

Nobody?