Round magnets are available in sizes from 1 1/4" to 3" (prices shown are for the 2 1/4" diameter) and the squares are 2" by 2".
The same selection of designs is also available on pinback buttons in a similar range of sizes.
Orders for merchandise from 'Ars Celtica' are filled by Zazzle. They're billed and shipped separately from merchandise ordered through the vendors who supply 'Saga Shirts' and my other products.