I see it frequently in America. It’s a homonym of the contraction would’ve, and similarly, other modal verbs like could’ve, should’ve, must’ve and might’ve. There is, however, no *can’ve or *will’ve in standard written English. I personally don’t contract can have that way in speech, but do contract will have. I’m not sure, but this might be because I do sometimes say things like “can of beans” and very rarely “will of the people,” whereas the closest thing to would that I might follow with the preoposition of is something like, “the wood of a sturdy tree.” So perhaps I subconsciously pronounce “can have” more distinctly from “can of.”
With negative contractions, won’tve and wouldn’tve are so rare that my spell checker doesn’t recognize either, but I pronounce the word have in wouldn’t have the same way as in would have, when they’re both stressed or both unstressed.
Another variant is “Woulda, coulda, shoulda,” or “Wooda cooda shooda,” which writes out phonetically an even more-reduced form of unstressed have. This is more informal than “Would’ve, could’ve, should’ve.” Be careful: not can be heavily reduced the same way, and “I canna” would be understood as “cannot,” rather than, “can have.”
Since there are many verb phrases that do use of (for example, “Be of service”), it’s an easy mistake for native speakers to make. It’s likely to become an accepted synonym of would have eventually, but is still considered an error by people of my generation.