If you could squeeze your board slightly to 50mm x 50mm, Chinese fab houses like Elecrow or Smart Prototyping could Supply your board for slightly less (about US$10)....for 10 copies! Yes, about a buck a bosrd for 2 layers, soldermask (possibly your choice bbq of color for no additional charge) on both sides, silkscreen on both sides.
If you can't squeeze it down to a maximum size of 50mm x 50mm, you can get 2 layer boards of up to 100mm x poll for about $15/10.
If your board is something you'll want to have more than one of, these Chinese vendors are the way to go.
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