To find true virulent antisemitism (folks likely to use terms like "kike", etc.) your best bet is to look on the right side of the spectrum.
I have to disagree there... these days the most hardcore anti-jew types are on the left, which is extremely ironic when jews for decades have been able to use the left as their personal army and have programmed the average leftist to spout whatever jewish talking points are popular at any given time.
This was made possible due to the hollowc0$$t and the jewish victimhood mentality which they have worked tirelessly to promote since WW2. They fucked up though with their antics in the middle east and lost the support of the people who previously had provided it unconditionally. It's a beautiful sight to behold and much deserved quite honestly.
That said, there are still a lot of anti-jew types on the right (myself included), but our hatred of jews isn't for the same reason. The far left anti-Israel types couldn't give a toss about replacement theory, if anything they champion it...