Morris Minor Owners Club

Been reading up on the heat shield underneath the passenger floor which most seem to think is an undesirable rust trap, so am looking at alternative. There are many suppliers of self adhesive tape/pads available, but wonder if this a possible alternative as I am at the stage of my project where I have to either ignore the issue or find alternative/fit the old original one.
Has anyone tried the alternative?

I think the original will be best if the car is kept dry and cared for.

I suppose it could be sealed around the perimeter with silicone or probably better a black mastic from a tube. Better to be done when replaced rather than seal in any moisture in an existing shield.

Don't know why there are two duplicate topics on this subject. Just read the other one and discovered the suggestion of sealant has already been mentioned.