That said, if you like the combination of traits from known breeds, you can start with people who raise those breeds and ask if they're aware of any litters that are an accidental or even deliberate cross. Check the adoption sites, put out word to the no-kill shelters and even the pounds as far as what you're looking for. You'll eventually find it.
“It can be a mistake to try to replicate a beloved older dog. They all have personalities and quirks above and beyond breed traits. Even if you were to find an apparent clone from outward appearance, there’s no guarantee that the particular drives and behaviors would be the same.’
I totally agree with RG — finding a clone — inside and out — of your beloved dog is probably not very likely.