Seeing one is easy; just find a
Yamaha Virago XV535. The LF400 is a straight copy of the (rare) sleeved 400cc version, shaft drive and all.
I say "copy", but I suspect Lifan bought the Virago jigs when Yamaha stopped making it, so for all practical purposes the LF400
is a Virago. I'd bet beer tokens that you could drop 535 pistons and barrels right in.
The exhaust is catalysed to meet Euro 3 requirements, and the ignition and carburettor may also be tweaked, but in looks and riding it's Virago all the way.