If you cannot pick up an old Kent on BST, then I would look at Simpson Super, an Elite Razor premium knot or a Maggard silvertip. I have heard that Plisson is similar but I have never used one. I feel you would want a silvertip knot with good flow-through and set at a high loft. FYI, I have 3 Kents; BK4, BK8 and BK12.
White Handle Silvertip badger hair shaving brush: The handle is made of resin and the hair is silvertip badger. Kont size25mm, hair height 55mm, handle height 53 mm, Wash with soap and water as needed and leave to air dry.
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I have one as well as a Kent BK8. The handle sort of resembles the Kent, but the important part, the knot, is every bit as nice as my Kent BK8. It will certainly provide a nearly identical experience.