A lot of the Scottish intellectuals I've talked to where pretty explicitly Marxist (including, but not limited to, my supervisor who had a poster of Lenin in his office). Also I think current SNP politics are pretty close to Marxism-Leninsim.
Yes, you can find Marxists in the UK. That does not at all change what I wrote. The narrative of Marxism as some big scary bogeyman in UK politics is an alt-right trope. Suggesting the SNP, which is only moderately left wing even by UK standards, is close to Marxism-Leninism is equally ludicrous.
Put another way: If Marxism had any prominent support in the UK, RLB would have been outflanked on the left in the Labour leadership elections, rather than losing to someone on her right.