Hi Charlie.
Sincerely I would go for a "home made" t-shirt. Usually I buy a blank t-shirt with a clean and nice cut. A low collar if possible.
And then choose an image and then request a print in a print shop.
Costs about 7-8 euros in Portugal (t-shirt=2,5+5=print).
I'll send you a pic of how it turns out. I've got one Felt shirt.