You have a couple options here.
The 26CT does provide the 75V/100V transformer with it $312.00
The 26C comes in at $270.00
with the tranformer that matches the JBL's output levels --
$27.50 for that.
Total is $297.50
I'm sure if you have other suppliers for the 100V 60Watt line audio transformers, you may get a better price, and can install them on the 26C speakers.
The reality is that you may get the 26CT faster if you haven't ordered the 26C yet. Cost wise, I think the 26CT is well within reason. The fact is the price is close enough on both, so you'll have to make the final decision on which choice serves you better.