Hey Rob,
They actually had a factory option/accessory 914/4 chrome tip too for the 1.7/1.8 & 2.0 (14s, & IIRC it's still shown in that 914 PET Parts Manual that you can download from the Porsche website, Classics section, under Documents.
You might try searching for the `60's 912 or 356 B/C Chrome Tip, since it's diameter is close to the 1.7/1.8/2.0 914/4's. IIRC the 912 ones may all be the early squared-off rolled tip - rather than round rolled.
Check with SMC & Stoddards, in addition to Sunset Porsche & Sunrise Porsche onlune parts departments.
Measure the diameter of your tailpipe section & have it on hand before you call or go online with the vendors, because they'll be measuring which non-914 tip is closest fit to yours.
Tom
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