The GAN Mini M Pro, it has a magnetic core, and is 53mm, and $33 on SCS.
The YJ Zhilong Mini M is good too, it’s 50mm, and costs $9 I think.
And last choice, the 54mm Dayan Guhong Pro, Standard or MagLev, it doesn’t really matter, it’s 54mm, so it should be good for solving.