Replacement hold-down clamp for Legacy battery

[hapless]

I've just replaced the ailing battery in my 54-plate GenIV and the hold-down clamp that keeps the battery located is badly corroded and needs replacing. I'm nowhere near a Subaru dealer to get an OEM part, but I'm sure there must be alloy ones I can buy online. It's the standard 005 battery, which I think is the same one used by Impreza of the same vintage, so the same battery clamp - any suggestions what to go for? Anyone who's replaced theirs, what did you use?

[S47]

WHy not make one?
You only need a piece of steel 25x3mm and drill 2 x 1/4" holes same spacing as your rusted orig, sorted

[Lefty]

I've got an RCM one:

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