If you're talking about the ones with the herringbone/checkered "Pepita" cloth seat inserts (black/white & black or white/black/brown on brown or tan), then Autos International in Escondido CA does them, & they know proper 914 interior fitment & do Concours P-cars of all models/eras.
http://www.autosintl.net/You'll have to figure 2-way shipping from the right coast if you want them to do it.
They also sell the raw fabric IIRC for a local shop to do it, & may also be willing to do their 914 upholstery kit in the Pepita to ship to you for local upholstery shop or DIY install.
I'm not sure, but 914Rubber may also be able to do a kit, if they can get the Pepita fabric.
Good Luck!
Tom
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