I've wanted a hand held laser rust remover for years but way above my pay grade. I like to rescue old machinery for a hobby and find a hammer for big flakes and a twisted dtrand wire brush on an angle grinder to remove the bulk works well for bulk removal. If I can then break into smaller parts I do and dump into drums of 40:1 - 60:1 Water/Molassas mix and leave. Pull out for an occasional scrub. I like the Molassas as it converts the rust to inert Iron Oxide including that in the pores.0Sand and Polish or if painting on cast iron in particular I coated with de-oderised fish oil then paint.
Molassas is not super fast but it is gentle and non-destructive to sound metal , super cheap and lasts for years.