Nothing stands up well to a 10 cavity.
When I was a kid I cast for the local sheriff's office. The sheriff had a huge pot that held about 3-4 gallons. No problem keeping up with a couple of 10-cavity H&Gs. I cast a
lot of 38 wadcutters with that setup.
My first lead pot was a 10# SAECO, it always seemed tiny to me. Been using an RCBS Pro Melt for 25+ years, lately looking into a Magna 40#. As always, it is a cost/benefit analysis. I'd usually rather have a new gun, but stumbling across H&G 8 or 10 cavity moulds for the pistol bullets I use most would change the equation.
Cost/benefit-wise, it might be most effective to pick up something like a Lee 20 to use as a premelter. Or get the SAECO fixed and use it as a premelter.