1 oz APMEX Bar
Cost = 40.40
Sale = 36.28
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Diff = 4.12
1 oz Silver Eagle
Cost = 42.04
Sale = 37.93
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Diff = 4.11
You're 1 cent ahead by going with eagles ( the margin used to be larger), not to mention easier to liqidate and possible tax advantages at time of sale. They're also legal tender and will always be worth at least $1. :)
BTW, Canadian 1 oz silver maple leafs have a face value of $5!
APMEX is overpriced for American Silver Eagles.
golddealer.com is reputable and is only $2.70 over spot (I think you can get 100 coins at this price)
A-mark is $2.30 over spot, for 5000 coin minimum.
For privately minted silver ounce coins instead of American Silver Eagles, nwtmint.com is $1.00 over spot, and they are reputable.