closing panel retainers

[trelogix]

Does anyone know of a good replacement for the 3746293 retainers that connect the "closing panel" and "support" to the inside of the front fenders? I've searched all over the place and can't find the actual retainer and the ones that I have left over are all rusted or broken. I'm guessing I'll need to use some sort of nylon push-type retainer instead, but I wanted to check here and see what other people have used.