Don’t want to make a broadband common mode choke yourself? I will gladly build one for you to buy. By the way, did you know a common mode choke is also often called an RF line isolator, 1:1 balun and 1:1 unun? Latter two for transforming a (un)balanced antenne to an unbalanced feed line.
Some variants I have built.

SO-239 UHF female

SO-239 UHF female

SO-239 UHF female
Specs
Frequency range:
1.8-30 MHz (160 m to 10 m band).
Common mode suppression:
25 dB around at frequency range edges to 45 dB at 14 MHz.
Power rating:
1000 W SSB | 500 W CW (single toroid)
2000 W SSB | 1000 W CW (double stacked toroid)
SWR:
<1.1:1 from 1.8-30 MHz.
Case:
weatherproof plastic ABS IP65, approx. 12 x 8 x 5.5 cm.
I can also build these with N or BNC connectors or for low or high band ops.
Buy on eBay or directly
Please contact me for details on price and shipping costs via the contact form below. Or drop an email via my email address on my QRZ.com page. My common mode chokes mare also llisted on eBay.
USA-based Hams, please read below the contact form:
For US Hams
Until recently, EU goods valued up to 800 USD were exempt from tariffs. With President Trump’s new import rules for EU products, tariffs now apply to every item. Because US Postal doesn’t have the capacity to handle all the extra paperwork, they no longer accept packages from European postal services.
US Postal’s only exception is packages marked as gifts. But even then, there’s no guarantee they’ll actually be treated as gifts. If not, the sender may be charged extra fees or penalties.
If you want me to build your common mode choke, I can now only ship with DHL Express. Keep in mind that shipping costs will be higher.