Cheapo twin probe Chinese C-Band LNBF will do for starters, get one for a tenner from Ali Express.
I would avoid them C/Ku combi LNBF's, performance has been reported as suffering on one band from what I have read.
If you wanna go for a more expensive twin probe LNBF then Titanium Satellite sell a few models, some with filters to reduce 5G/WiFi interference.
If you wanna go reet top end then get a C-Band orthomode and stick a pair of Norsat 3120 LNB's on it.
Check out the C-Band sub section on the form to see what other members have achieved with their dishes.
A 1.8m dish correctly aligned should be getting close to 200 channels from 40.5W and getting some locks from a lot of the C-Band satellites visible to a UK installation.
Throb On... the world of C-Band is calling now that you have escaped from the world of the mini dish men with your 1.8m Channel Master.
Dish Man classification table attached below.
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