Do you need an RDM or SDM extension? I for sure have spme spare RDM extensions that would match with a base that I would let you just have. Not sure about SDM but I will check as well.
Less likely to have a good match on boards, I do have an RRD Firemove 135 that's just a couple years old but I really like it so last time someone wanted it I was asking $1100. I will keep an eye out for you though. If you want more info, email is best: kristian462@gmail.com