6809 was the best 8-bit microprocessor ever made, I ordered a couple while they are still available.
I used to program on a 6809 as well. How about we make a retro dual processor (09/Z80) board 
compatible SRAM and some program storage memory that is relatively easy to program as I have no idea where my EPROM programmer has gotten off to. Any recommendations welcome.
There's plenty of SRAM around these days that will work. As for the EPROM, maybe use flash or just battery-back the SRAM. You could build in a modern micro to act as a programmer.
Another idea is to have an modern micro actually serve the EPROM data.
Rob