I would greatly recommend moving to a VPS. It is more complicated since you're responsible for the software running the webserver but once you get that down, you suddenly have a lot more power and arbitary limits like how many sites you can run are removed (since their existence is with shared hosting limitations)
Plus, it's cheaper. I don't know why you're hosting a flarum install, but if you're doing it for a small group / test environment for yourself, 512MB is major overkill.
As a con(ish), you're responsible for much more and destroying all your data would probably result in a "use your backups to restore". So you know: low power - do less | easier <> Full power - do more | harder.
Anyways to answer your question -
I'm personally using ramnode - they've got a solid track record and have been great with me. You can get a 512M, but if it's just for yourself / small group, they have 128M ones for about $1.25 / month ($15/yr) (plus there's coupons)
