If you are looking for double-thick paper coasters, here are some options to consider:

1. Online printing services: Many online printing companies offer custom double-thick paper coaster printing. Websites like Printful, Printify, and UPrinting allow you to upload your own design and order coasters in bulk quantities. These platforms often provide various customization options, such as size, shape, thickness, and finishing options. You can choose the double-thick option to ensure a sturdier coaster.

2. Local print shops: Visit local print shops in your area and inquire about their custom printing services for paper coasters. Some print shops may have the capability to produce double-thick paper coasters according to your specifications. Discuss your design requirements, size, thickness, and quantity with them to get a quote and ensure they can meet your needs.

3. Specialty coaster manufacturers: There are manufacturers that specialize in producing custom paper coasters, including double-thick options. These manufacturers may have a wider range of thickness options available and can work with you to create custom designs. Search for specialty coaster manufacturers online and contact them to discuss your specific requirements.

When ordering double-thick paper coasters, consider factors such as paper quality, print quality, customization options, pricing, and turnaround time. It's also a good idea to request samples or proofs to ensure that the final product meets your expectations before placing a bulk order.