The Officially Licensed Right Podcast Store
Just kidding. There is no store.
The images
As is the case with all links these are not necessarily endorsements. I'll add images that can be used for whatever you'd like. Make your own shirts, stencils, pins or use the innumerable services out there that will help with it.
A series of videos that show how to silk screen t-shirts: DIY PUNK Screen Printing: Step 1 - How to make the screen - YouTube
Tutorial: How to Screen Print Your Own DIY Band T-Shirts Tutorial: How to Screen Print Your Own DIY Band T-Shirts (sonicbids.com)
Tutorial from HP for making iron-on-transfers. Check your make/model page: HP printers - Printing HP iron-on transfers (mirror Images) | HP® Customer Support
Suggestion: If you're going to be creative and go down this road check for ethical/unionized t-shirt companies. There are many to choose from. If these links break (please let me know) but there are also many great articles blogs and videos for silk screening.
Ideas to download/screenshot for your own memes, crafts or to upload for t-shirt printing elsewhere.