Really nice loco! Brasseur Electric Trains bough much of remaining K-line inventory and can help: https://traindoctor.com/service/kline/kline.php I'd suggest giving them a call or sending an email.
I believe it is one of these drawbars but I'm not sure. Maybe another OGR member can check their K-line Mikado?
If you find the need for any other parts, you may be able to order some used on the Lionel USRA Mikado (which is re-issued K-line tooling.) Just note that the electronics won't be compatible. In this case the Lionel version uses a wireless IR drawbar, so unfortunately that's not a viable replacement.