These plugs have NO hole. 
​Solid Rubber Stopper plugs for fountain drainage holes

These plugs have no hole and are solid rubber that taper down
Plugs come in 7 different sizes.
 

• A1 Size: 1" top tapers down to 3/4"     ($2.95)
• B2 Size: 1-1/4" top tapers down to 1"         ($3.85)
• C3 Size: 1-3/8" top tapers down to 1-3/16" ($4.25)
• D4 Size: 1-5/8" top tapers down to 1-3/8"   ($4.95) 
• F6 Size  2"  top tapers down to 1-5/8"         ($5.95)
• G7 Size 2-1/8" top tapers down to 1-3/4"    ($6.25) 

To determine which stopper you need to plug your existing hole, measure across the opening and this measurement will be the plug size you need. 
If in doubt, get the next size UP.

To order stoppers with a hole, they can be founsd here: https://www.fountainsnslate.com/inc/sdetail/17801