Alas, no parts to offer, but should you end up wanting or needing to scratchbuild one, there's a great resource here. Very useful photos, drawings and clear descriptions of different installations.
I know of no aftermarket stuff in that scale. I had a Tamiya 1/25 Tiger years ago that included a decent radio, so you might be able to scavenge one from somebody's old kit or built-up. Good luck!