I envision using them in several older Weaver SD-40's and pre-TMCC Lionel diesels, just as Ron plans. So I would commit to minimum of 6 assembled boards, and likely 5 more after I get the first batch installed. These should also work well with your sound board, right John? I would need to get you to Fedex them, if possible, just to avoid the whole cross-border mail thing.
I would also take perhaps 5 bare boards for minimalist installations, without all the functionality.
Rod