Load up on some Zdzisław Beksiński prints:
Was going to be my first recommendation. Here are some more I thought you might like. Little tough when it comes to this since it's so personal, if you can narrow down a direction to head toward I can get more specific. Names link to profiles or websites, the other links are to the individual artwork posted. Will grab more after food and stuff.
Jacob van Loon |
linkStill some stuff near your price range on his Big Cartel, + some original panels. Can always check for refreshes, too.

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Junyi Wu |
linkNot a lot available online but if you're interested I can put you in touch with her for originals or reprints.

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Julian Callos |
link
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Alex Kanevsky |
linkI honestly don't know where to buy Alex's stuff, you might want to try contacting him directly because I know he does print runs.

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Kevin Wada |
linkYou like Gundam, right? Kevin does a lot of pop culture illustration, he's really good. Takes commissions although it's slow, and you can contact him directly with questions/for reprints. Super cool guy when it comes to working with people to get them what they want, too.

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Alvaro Tapia Hidalgo |
link
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