Short period of time like 24 hours, sure? Short period of time like "I hope I'll get to it soon", no.
Yes, it looks like you need a new wet side. The new MP40QD wet sides are compatible, and are a better design as well. You might be able to find a used MP40 wet side and swap the magnet (it isn't hard), but IME most failures that take the wet side out of service involve a ruined magnet coating in some shape or form (melted, worn through, cracked, etc.) so your odds of finding one aren't as good as if you needed say the impeller or cage.
ETM doesn't list a wet side magnet as a part, but it would be interesting to see if they would sell one over the phone. Purchased used I suspect not, but it never hurts to ask (and report back for the rest of us).