not sure how anyone could be patient with silver off 46% from the top.
The price does not reflect value.
The brokerage I use doesn't offer it to my knowledge. If I'm going to take delivery of certs, I might as well just buy physical (which I have the percentage I want in physical). Sides none of my brokerage accounts are over the insured limits. So unless my online brokerage and the federal government fail at the same time, I'm pretty safe. If they do fail at the same time, its likely my certs or direct registered shares are worthless as well.
If you really want security, hold the metal in your hand

The point is that you would probably do better to have shares vs. something someone on the other side of a naked short gave you in lu of a share. The differences in how these two distinct items are treated in the years of lawsuits which would follow an implosion of your broker (in the hopeful case that we have a functional justice system to adjudicate such things) could well be significant.
But do as you will. I'm not yet to the point of even wishing to play with jr miners even though, as you say, it's getting pretty damned tempting. OTOH, it's been tempting for many years and I have yet to regret not 'jumping in it.'
A brokerage is not the deciding factor of direct registration. If a company handles share issuance in-house or uses a transfer agent, it is dependent upon the company or its transfer agent.
The real issue is not whether your broker or the gov't fail, but whether your shares have been lent out. In that case, rehypothecation may come into play. If you do not have your shares entered as book entries with a 3rd party other than your broker (the respective company or transfer agent), you will have difficulty establishing ownership and retrieving your assets - if you even have any hope of getting them back at all.
If it's your word against your broker or a firm claiming rehypothecation rights, you are screwed. If you have a 3rd party with independent confirmation of your ownership, you will be at the front of the line for claim payout.
Government is never a guarantee!