Charlie England wrote:

Try your local Home Depot 'A/C supply'.

Go to the insulation section & look for 'aluminized mylar' radiant barrier
insulation. It comes in various forms. Best for you would be the mylar sheet
with an aluminum foil bonded to the mylar. Other types may look like either
bubble wrap or foam wrap sheets for protecting delicate stuff for shipment,
but will still have the aluminum foil coating. More durable than just foil;
you can make a 'boot' by stitching a sheet into a cone shape.

Ron Wanttaja replied:

Neat idea, thanks, Charlie. Don't have a Home Depot A/C Supply real close,
but Lowe's Aerospace is right across the road from the airport. :-)

It probably isn't an issue in Ron's case, but having recently seen the Nova
program on the investigation into the causes of the crash of SwissAir #111 I
feel compelled to point out that some aluminized Mylar insulation is
flammable.

Russell Kent