It would actually work just fine
assuming it is cantilever no problem.
It would be a bit more stable at speed
meaning a bit less nimble at lower speeds
but it would work fine-done it-
Now bigger rear wheel/tire-might make the handling a bit trickier-but bigger front-no problem.
Not as if bikes are Formula 1 motorcycles or cars-
It doesn't mean carrying 2 different tubes??

Another fork will be another $30 or more-IF you get lucky-
give it a try-it will work just fine-nice stable ride-and sorta cool/odd looking