Also Ric, in addition to used ones -
I don't know what your budget is, but Dansk/JP makes the current OEM 2.0 muffler, & is available at most any P-dealer or P-parts house, but shop for price & sales. Last I saw they were about $700-800 new, & less 10-25% on sale.
Sunset Porsche in OR & Suncoast Porsche in FL usually have the best dealer price, & Sierra Madre, AA, Stoddards, etc. often run sales.
PS - Unless you can have someone check it out in person for you far away, or you personally on local to you - a used one could just be a bunch of rusty crap inside - even if it looks solid outside. So that used one for $390 could easily be a worthless POS (I don't know it), whereas the new one will probably last you the lifetime in which you own the 914.
PSS - An NOS one will be about the same as new, or a bit more if a Leistritz Sport Muffler - they & Bischoff made the original OEM ones for Porsche-VW in both stock & sport variety (Bischoff may not have made sport type).
Tom
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