Hello and welcome to Just Answer. My name is ***** ***** I will be happy to assist you with your electrical question.
1) I doubt that you will be able to locate replacement parts at any of the big box home improvement stores. I've never seen just the plastic globe being sold and stocked at any Home Depot or Lowe's. More than likely, you will end up purchasing the entire light assembly.
2) Shown in the link below is a source for purchasing a replacement unit:
3) The only other option would be to contact Intermatic directly and they may possibly be able to sell you just the replacement globe piece.
See link shown below for Intermatic contact phone numbers:
If you have any additional questions, just let me know and I’ll be glad to answer them for you.
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