That would depend by the type of cells you use, but you can try cyclophilin-A, vinculin or HSP 90. Actin would be maybe too close to the tubulin band, but it's up to you whether you want to try it or no.
as an alternative to staining for loading control, you can use the TGX stain free pre-cast gels from Biorad. Article V3 Stain-free Workflow for a Practical, Convenient, and Reli...