Lo and behold...I found the slide idea we did at the field test.  There doesn't seem to be the plastic ring but the front animal cutout is just like the ones here:http://www.e-scoutcraft.com/leather/leather.html

I also found another source for slotted conchos like discussed on the old board and here: http://www.tandyleather.com/products.asp?dept=124

Just thought I would share!