Some tyre garages have machInes the can straighten them. Where I work to anyway. Depends how bad the buckle is aswel.. Heat it up to about 60 degrees with a propane burner and hammer it if you cant find anywhere.. Just make sure you keep heating it! Also if it isn't to bad some places do a dynamic balance.. Where i work it's called an 'alu 3' setting. Try kwik fit, think they use the same balancers