Possible material for RF splitter mirror replacement ?

This item is currently on sale at Surplus Shed (I have no relation with them other than one-time customer):
http://www.surplusshed.com/pages/item/l14550.html
I guess one would have to remove the gold coating except on the RF patch, and replace the whole splitter plate at 45°, then recalibrate the RF. Easier said than done, but still easier than cooking a half-reflective coating in your kitchen. Or, maybe, leave the whole plate as-is and have a "full-frame" RF patch.

If I remember well, beam splitter plates are fully covered, no need to remove anything, just cut it at the correct dimension.

I've got a use for a couple of them, but international shipping would be a bugbear....

Half-reflective mirrors are obtainable off the shelves from glass coating companies.

@paul_c5x4 : PM me.
@ AgX: Sure, but look at prices:
http://www.edmundoptics.com/optics/beamsplitters/plate-beamsplitters/plate-beamsplitters/2035
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