You could just ask most any member of silvergoldstackers (aka steemsilvergold) 😉.
There are tons of reputable online dealers. Apmex, monarch precious metals, bold precious metals, provident metals, vulture peak mines. Before the pandemic most of these dealers offered 10oz at spot deals for first time buyers in the websites. With demand for silver fairly high now those deals are harder to find.
Kilo bars are hard to sell and harder to store. In an “oh shit” scenario unloading smaller pieces is easier. If you are stacking just for weight, low premium and not collectibility it might be worth it to you to just buy a roll of generic one oz rounds.
Silver spot price at the moment is kind of dumb though. Rounds that sold for $17 or $18 at the start of the year are selling for $30 now. Great if you are already invested and looking to sell. Not so great if you are just starting. In some ways being into collector coins might be better now. Spot could easily drop meaning generic silver could quickly lose value. Collectible stuff might hold value at today’s prices better.
But I am no investor or financial advisor as they say. I just buy silver I like when the cost and my desire to own a piece match up.
@raybrockman has been pouring awesome silver lately. You should check it out on the silver gold stackers discord. He has been known to accept hive and steem for his pours. (Ray is a long time member of the silver gold community on steem/hive).
I got an 8.45oz pure silver sugar skull from Ray a couple months ago at spot ($18.59 at the time) and paid steem! It felt like getting metal for free. 😄