We are mostly Canadians on this forum so I don't know if any of our members would have any expertise on these. I think most of the forum members collect primarily Canadian insulators although many would have American made pieces that were used in Canada in their collections. If I'm not mistaken, EC&Ms were primarily used in the SW US, maybe even limited to California. I will tell you that these are broken down in the price guide by the individual mold that they were poured in and a certain amount of expertise would be required to identify it from the photos.
If you want to avoid 'making rookie mistakes' (especially potentially expensive ones) I would suggest some or all of the following:
1. get a copy of the
price guide2. get to know your way around
ICON (picture poster, articles, lots of good info)
3. check out the
CJOW archives (notice the search link near the top left)
3. find a mentor in your area
4. attend insulator shows/swap meets
5. consider starting out with more common insulators while you learn
6. by all means ask questions here (but cut us some slack if we can't answer them all
)
Not exactly what you were looking for, but I hope somewhat helpful.