Hi, I painted my own :-). I searched online for "simple abstract painting of xxx" or something like that, or "paint yourself xxx". I found loads looking for seascape, canyons, some other categories. Blew them up for the outline, transferred to canvas with pencil, paint. I genuinely traced the scale templates directly from my PC screen onto baking parchment to cut out.
The Works does good priced canvases and paint. One nice thing is that if you don't like it you can actually take a scourer to it gently if you've used acrylic if you don't like the overall result, or if you make a mistake.
I stuck to super simple, monochrome things but instead of black on white you can make it blue on green etc. For splodgy painting kind of abstract no harm in throwing some colours at it!
Also charity shops for actual canvas can be cheap and just paint over whatever is there maybe with normal decorating primer to begin.
A friend has an example (real original art though) that genuinely could possibly be reproduced with some textured random spreading of decorators caulk on canvas or board and painting it all one colour.
B&M also has great value big tubes of acrylic.
You know for SURE the result is going to be original art!
Hope that is helpful - I've even been commissioned to do more for friends!