I may be wrong, but I think you would have to go quite a long way 'up market' until you found one that did. I've had many multimeters over the years/decades (and currently have a good few, but I have personally never had one that can measure AC mA (and I'm not even certain about AC current at all).I did consider that but my (extremely) cheap and nasty multimeter doesn't do AC current.
In any event, as I have said, a multimeter wiuld not be useful in the case of a boiler, anyway, since it could only measure current in the CPC (earth) of its connection, and that is no good when leaks to earth may be going, at least partially, through other paths.
Kind Regards, John