Yes Jeff,
Generally you could've gotten any radio sold in <73-74 in a 74 MY 914, since most were dealer or aftermarket sold here in the USA, plus I think these were also a factory option (double check at Jeff Bowlsby's site's Options webpage list). That would include Porsche, Audi, VW & just about any other units (Motorola made many for the P/A/V accessories group VCP).
IIRC though, you'll need the 914-specific faceplate with the notch in the top right to clear the glovebox lock (or maybe not ... test fit it).
If the molded plastic faceplate to look like the dash face's vinyl basketweave (70-74) or brickweave (75-76), then they'd just use the metal closing plate with a cut piece of the vinyl adhered with interior adhesive instead. Most of the 911/912 & 914 parts suppliers sell small rolls &/or kits of the vinyl, or you can use scrap from you project or a local upholstery shop.
If you can find the plastic one, they usually look & fit better.
Tom
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