In article . com, David
P writes
The Ikea ones fit inside a 50mm carcase, or 100mm carcase (minus the
18mm each side)

I presume you mean 500mm or 1000mm (as 50mm, minus 2x18mm, is quite
narrow).
My problem with Ikea is it's a 2 hour round trip from here, with no way
to check if they actually have what you want in stock.

I've looked in all the sheds but none of them seem to do anything like
that - probably not trendy at the moment.
--
Tim Mitchell