Many libraries around me in the Bay Area seem to have 3D printing services for free — this might be an alternative for a one-off, while costing you nothing!
Shapeways have been around for ages, and I've always been satisfied with all their options.
The lowest price I can see when I upload my stl is $150, which is quite a difference from $30. Maybe I'm doing something wrong.
Are you willing to share the stl/general geographic area? I might be willing to print & ship. There's also https://old.reddit.com/r/3Dprintmything/ if all else fails.
I appreciate the offer but I already have it and don't need another right now (the onshape project is also linked if you're interested)
Thanks for the subreddit link though, it could definitely be useful in the future.