Personally I'd not bother with badger knots. I sold all my badger brushes last year and haven't looked back, modern synthetic knots are easier to use and whip up fantastic lathers they're also easier to look after long term.
Here's a few commonly available in the UK synthetic brushes I'd personally recommend that won't break the bank
Phoenix Artisan (The Starcraft brush is one of my favorite brushes):
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Simpson Trafalgar T2:
Simpsons Trafalgar T2 Synthetic Shaving Brush
shavingstation.co.uk
The Yaqi synthetics are decent given how cheap they are so they're a pretty safe bet as well.