can't find an item,hope you know

Hello,someone just told me about this group,and did I needed one in the
past many times.
My sis has an antique front door with recessed (6 glass) pannels and
decorative molding,she don't want to remove anything on the door,
but had me make her 6 stained glass pannels,
to fit over the existing glass & molding, into the squares.
Since its a front door and grandkids like to slam doors,we need triangle
corners 4 for each picture,
to hold in place inside over the plain glass.
Tried several things but need some corners aprox.1-1/2"x 1" that nail or
screw in with tiny screws.
Found plastic ones in hobby lobby,think they are for scrapbooks,tried to
make some out of clear plastic and metal,but they dont look very nice.
Seen them before ,but can't remember where,as I had no need for them at
the time.
Also have to downsize due to move into a tiny apt,
is there a place to list stained glass related items for sale,
and where would that be.Tried glass source,but can't post with webtv,
and no one with a pc.
Had a nice member list for me,but it's bad when not able to respond or
correct.

Think most people looking for used grinders ,bandsaw etc.
wich I don't have for sale,
only bevels, came ,petina,grinder bits,putty,etc.
Hate to list on e bay,as I have always bad luck with getting the right
categories,as a fact have a hard time getting on with my webtv.MD