Worm gear on window crank has come loose

Howdy, As seen in 2 photos, the worm gear on left hand window has broken,come loose, etc. The arm attaching under the sash is marked 30744. Please tell me part numbers I need to order. You can crank window out but then the crank and worm come out when reversing to close the window. Glad there is a deck outside - just walk out and push window closed. Glad it is not on 2nd floor LOL. Sold Marvin for many years so very familiar with Truth Hardware. Sad to see all the import jumk arrive in early 2000's. Picture have necessary dimensions on them. Thanks in advance...