Sorry, but you won't be able to get a Penny Black for anything under $100 -- unless you are very, very lucky and find one on e-Bay that no-one else bids for. I get lots of catalogues from stamp dealers in the UK, and the minimum price for a Penny Black is about $180. And then you can pay up to $50,000...or probably more. As I'm sure that you know, the price of any of these early plate stamps depends on the plate number, the position on the plate, the colour, the condition, the postmark (if used), the margin, the number of plates printed etc.
Perhaps you should focus on Penny Reds (I do). They are much cheaper -- from about $1 -- and there are many, many more of them around than Penny Blacks. I have about 500 Reds, but only 2 Blacks.
Your "Year of the Black Snake" stamps are great. I'll send you some of my stamps in exchange for the Black Snake stamps. Do you have perforator?? Myself and a good bought one about 8 years ago. You're a great artist. BF.
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