<hijack warning>
Victor and Stanley signed the inside of my Distillate backplate when they toured together (pre-SMV). Sometime after that I had Mike Watt sign it… he had so much fore arm sweat that it smeared Stan’s signature! Oops. I guess Sharpies aren’t that permanent. 😄. (and Mike Watt doesn’t hold back when he performs!)
FMM has sound advice, if Mica can’t source one for you right away, check your local Machine Shops (alternative material other than brass could keep the price down). You also could try wood glue and some fancy clamping…
Good luck. Keep us posted.